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A swinging and spinning amusement park ride has broken apart on the opening day of the Ohio State Fair, hurling people through the air, killing a man and injuring seven others.

Three of the injured were in a critical condition, authorities said.

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'The fair is about the best things in life and tonight with this accident it becomes a terrible, terrible tragedy,' said Ohio governor John Kasich.

The man who was killed was one of several people who were thrown off when the Fire Ball ride malfunctioned, Columbus Fire Battalion chief Steve Martin said.

Dramatic video captured by a bystander shows the ride swinging back and forth like a pendulum and spinning in the air when it crashes into something and part of the ride flies off, throwing riders to the ground.

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A company providing rides at the Columbus fair this year describes the Fire Ball as an 'aggressive thrill' experience.

On its website, Amusements of America says that since its debut in 2002, the Fire Ball has become 'one of the most popular thrill rides on the AOA Midway'.

The company description of the ride says it swings riders 40 feet above the midway while spinning them at 13 revolutions per minute.

Mr Kasich said he had ordered a full investigation and all fair rides to be shut down until additional safety inspections can be completed.

In a post on its Twitter page the fair said: 'There has been a report of a ride incident. We are investigating and will report information as available.'

The Ohio State Fair runs until August 6.

State director of agriculture David Daniels said all the rides were checked several times when they were being set up to ensure it was the way the manufacturer intended.

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'We started out today with 11 rides that did not open because the inspection work was not done on them,' he said.

Mr Daniels said four rides would not be operating because they did not meet the mechanical test.

Ride inspectors said the Fire Ball was inspected at a couple of different stages and signed off Wednesday.

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One dead after Fireball fairground ride sends riders flying through the air

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A swinging and spinning amusement park ride has broken apart on the opening day of the Ohio State Fair, hurling people through the air, killing a man and injuring seven others.

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Biomechanical analysis of hammer throwing: assessment of speed development - ResearchOnline@JCU

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Study one focused on assessing the relationship between the hammer's linear speed and the thrower applied cable force. This was done to identify how cable force magnitude and direction affects the speed development, specifically losses. Speed losses occur when the tangential component of the cable force (tangential force) is negative.

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Senior Capstone Project by Brookfield High School Students Monica and Samantha Mazur

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Hurricane Harvey from the International Space Station on August 28. NASA, CC BY

Hurricane Harvey has taught us many lessons, but the most valuable may be the oldest lesson of all, one we humans have been learning - and forgetting - since the dawn of time: how much we all have to lose when climate and weather disasters strike.

The risks we face from disasters depend on three factors: hazard, exposure and vulnerability. In the case of Harvey, the hazard was the hurricane with its associated winds, storm surge and, most of all, rain. Houston is one of North America's biggest metro areas, making 6.6 million people exposed to this hazard. Finally, there's our vulnerability to heavy rainfall events, in this case exacerbated by the city's rapid expansion that has paved over former grasslands, overloaded critical infrastructure, challenged urban planning and limited evacuation routes. These three factors explain the immense costs associated with tragedies like Hurricane Harvey.

As atmospheric scientists in Texas, we already know the hazards are real. Once the effects of Harvey have been added up, Texas and Louisiana will have been hit by more billion-plus dollar flooding events since 1980 than any other states.

We also know that many of these hazards are intensifying. In a warmer world, heavy precipitation is on the rise, which increases the amount of rain associated with a given storm. Sea level is rising, worsening the risks of coastal flooding and storm surge. At the cutting edge of climate research, scientists are also exploring how human-induced change may affect storm intensity and the winds that steer the hurricanes.

This is why catastrophes like Harvey - in which every extra inch of rain can lead to additional damage and harm - highlight exactly how and why climate change matters to each and every one of us.

Sensible response?

People know the climate is changing, but they don't know how serious it is. Over 70 percent of Americans agree that the climate is changing, but less than half of us believe it will affect us personally.

Why? Perhaps because the image we associate most often with a changing climate is not the devastation left by a flood in our own state but rather a polar bear perched on a chunk of melting ice or an African farmer bearing silent witness to the impacts of a disaster that's taken place on the other side of the world.

As tragedy unfolds, we must focus on the immediate response. But in the weeks and months that follow, we need to remember that, despite our air conditioners, our insurance and the politicized discourse that suggests that the science is somehow a matter of opinion rather than fact, we are incredibly vulnerable to natural disasters - disasters that are increasingly being amplified in a warming world.

AP Photo/Gerald Herbert

What sensible, pragmatic, bipartisan steps can we take to increase our resilience to risks that a disaster like Hurricane Harvey represents? This question must be asked, because the current administration has proposed cutting the budget of the National Weather Service and other agencies that study and forecast weather and climate disasters and has rescinded regulations designed to address rising sea levels when constructing infrastructure.

First and foremost, we should reduce our exposure and build resilience to the hazards we already face today. We can't continue building in places that we know will flood. We need to build and modernize infrastructure to make our water management systems more resilient to both floods and droughts. We must continue to invest in the weather forecasting systems that provided advance warning and in the public services that build community resilience and provide disaster response.

Ultimately, though, even these practical steps may not be enough. In a changing climate, building capacity and resilience to cope with today's risks leave us unprepared for future extremes. That's why, in order to reduce the risk of disasters both here and abroad, we need to minimize the climate change that is turbocharging these events. And that means reducing our emissions of the heat-trapping greenhouse gases.

Changing the risk equation

Here again Texas can lead the way. We're already number one in wind power production by state, thanks to targeted investments that boosted the power grid connecting cities with windy regions. And we've only begun to tap our abundant solar resources.

The innovations that energy companies have pioneered to build offshore oil platforms can inform the development of, and investment in, offshore wind turbines and their knowledge of producing petrochemicals could be applied to more sustainably produced biofuels.

There will always be those who claim that the costs of moving to cleaner energy sources and reducing carbon emissions are too high. But the U.S. has improved air quality in ways in which the benefits greatly exceed the costs and replaced ozone-depleting chemicals, all while the economy has grown.

Today, wind and solar power prices are now competitive with fossil fuels across Texas. Across the country, these industries already employ far more people than coal mining. Electric cars may soon be as affordable as gasoline ones and be charged in ways that help balance the fluctuations in wind and solar power. Only someone profoundly pessimistic would bet against the ability of American ingenuity to repower our economy.

Hurricane Harvey exemplifies the risks we all face - and a more dangerous future if we don't take actions now. More people and vulnerable infrastructure exposed to more frequent and intense hazards equals even greater risk for us in the future. The time to rethink the equation is now.

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What Hurricane Harvey says about risk, climate and resilience

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Hurricane Harvey has taught us many lessons, but the most valuable may be the oldest lesson of all, one we humans have been learning - and forgetting - since the dawn of time: how much we all have to lose when climate and weather disasters strike.

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Oil refineries and chemical plants across the Texas Gulf coast released more than 1 million pounds of dangerous air pollutants in the week after Harvey struck, according to public regulatory filings aggregated by the Center for Biological Diversity.

While attention has zeroed in on the crisis at the Arkema chemical plant in Crosby, Texas, other facilities -- oil refineries, chemical plants and shale drilling sites -- have been reporting flaring, leaks and chemical discharges triggered by Harvey.

Emissions have already exceeded permitted levels, after floating rooftops sank on oil storage tanks, chemical storage tanks overflowed with rainwater, and broken valves and shutdown procedures triggered flaring at refineries.

The chemicals released in the week after Harvey made landfall include benzene, 1,3-butadiene, hexane, hydrogen sulfide, sulfur dioxide, toluene and xylene.

All seven chemicals are toxic air pollutants documented to harm human health; several cause cancer. Other emissions would bring the total to more than 5 million pounds, the Center for Biological Diversity said.

"Our general concern is the fact that these are relatively unseen environmental threats that don't normally get recognized," said Elena Craft, a toxicologist at the Environmental Defense Fund.

Further damage and emissions across the region could be uncovered in the coming weeks as flood waters recede, and chemical safety experts warned that restarting plants could carry as many dangers as the shutdowns.

"We are not out of the woods yet, not the entire industry," said M. Sam Mannan, a professor of chemical engineering at Texas A&M University and director of an institute that studies safety procedures in chemical factories.

In addition, winding rivers overflowed and washed over some of the waste pits and drilling pads at shale gas and shale oil drilling sites in the Eagle Ford play in central Texas, according to satellite imagery collected by Sky Truth, a non-profit group. The extent of the damage was not clear.

"It's unsafe and unacceptable for the petroleum industry to be releasing these massive quantities of air pollutants when storms hit," Shaye Wolf, climate science director of the Center for Biological Diversity, said. She added that the companies could do more to limit flaring and leaks. "That shouldn't be common industry practice," she said.

Companies have two weeks to submit filings to the Texas Commission on Environmental Quality so those figures could increase substantially. But the filings so far give a good picture of some of the problems.

The most common problem in oil refineries has been floating rooftops on storage tanks. Because petroleum is flammable, open space in a tank would collect dangerous vapors. So the oil industry storage tanks have round lid-like rooftops that rise and fall with the level of liquid in the tanks. With heavy rains, many were damaged and sank from the weight, leaving crude oil or petroleum products in the open air emitting fumes. In some cases, they have caused spills too.

Rooftops sank at four tanks at the Pasadena products terminal of Phillips 66. Three sank at the Pasadena terminal of Kinder Morgan, a pipeline company. Two were damaged at Shell's Deer Park refinery. One each sank at Valero Partners' Houston terminal, Marathon's Texas City plant and ExxonMobil's Baytown refinery.

Shell said one leaky tank, discovered during cleanup operations, allowed oil to run out into a surrounding berm. "The leak has been isolated and we're in the process of cleaning it up," said Shell spokeswoman Kimberly Windon, who added that there was "no offsite impact."

Flooding has posed other challenges. For a week, BASF, the second largest producer of chemical products in North America, has been struggling to contain rainfall at its Beaumont Agro plant, according to BASF's filings with the Texas Commission on Environmental Quality. The plant produces pesticides, herbicides, and insecticides.

The company started trucking waste water off the site the week before landfall in an attempt to maximize water storage capacity. Then, unable to contain contaminated storm water and process waste water, the company shut down operations on Aug. 27 and brought in temporary water storage capacity. Nonetheless, the tanks overflowed, spilling chemicals into a diked containment area. The diked containment area then overflowed to the surrounding ground.

Roberto Nelson, BASF'ssenior manager for community relations, said a test of leaking waste water on Aug. 29 "indicated there were trace amounts of non-hazardous process chemicals in the discharge water." He added that the overflow stopped on Aug. 31.

At ExxonMobil's Beaumont oil refinery, oil flowed over a 10-foot levee and spilled onto a nearby county road, due to the rising Neches River, an ExxonMobil spokeswoman told the local newspaper, the Beaumont Enterprise. A different spokeswoman, Suann Guthrie said the company was "closely monitoring" and "taking steps" to contain two sheens.

Oil and chemical companies have also been flaring large amounts of gases, beyond levels ordinarily permitted by the Environmental Protection Agency or TCEQ.

On Sept 2, the TPC Group said in a TCEQ filing that it was working to control the source of gases being flared at its Port Neches, Texas. It has already emitted an estimated 1,000 pounds of carbon monoxide and 1,000 pounds of nitrogen oxides, well beyond the state's permitted levels. Nitrogen dioxide is an air pollutant by itself, and also reacts in the atmosphere to form ozone, which contributes to breathing problems, and acid rain.

Huntsman Petrochemical on Sept. 2 reported it had flared an estimated 1,000 pounds of methyl tert-butyl, used as an oxygenate in gasoline and regulated in some states. The flaring exceeded the Texas limit of 0.04 pounds an hour.

Total said in a filing Friday that its petrochemical refinery in Port Arthur had no power and over a 48-hour period had flared half a dozen chemicals, including sulfur dioxide in one flare that was 50 times greater than the regulatory limit.

"A facility that shuts down may employ flaring of excess gasses that cannot be processed," Cal Dooley, president of the American Chemistry Council, said in a statement Thursday. "Flaring is an approved way to safely relieve pressure during a unit shutdown and is considered an industry 'best practice.' These controlled releases are done with the permission of state and federal regulatory authorities."

Texas is the nation's largest producer of chemicals, with $129 billion in shipments and 79,000 employees, according to Dooley's group.

Mannan, the chemical engineer at Texas A&M, last year authored a study ranking Houston-area facilities by their potential to cause harm to the public during a disaster. He said restarting production at dozens of waterlogged plants poses enormous risks for workers and the public.

"Additional events could happen because, if you think about it, a lot of these tanks got submerged in water and a tremendous amount of force is created in 40 feet of water. It can move the tanks around or deform them," he said.

"Every piece of equipment, every tank, has been battered by the flooding," Mannan said. "You have to go through and check every piece of equipment. A lot of hard work is still left, and a lot of potential for incidents is still there."

The Chemical Safety and Hazard Investigation Board on Friday issued a "safety alert" urging oil and chemical facilities to take special precautions when restarting after Harvey.

"Restarting a refinery poses a significant safety risk," said CSB chairperson Vanessa Allen Sutherland.
(c) 2017, The Washington Post. Steven Mufson wrote this story.

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Hurricane Harvey aftermath: Chemical companies already released 1 million pounds of extra air pollutants

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Oil refineries and chemical plants across the Texas Gulf coast released more than 1 million pounds of dangerous air pollutants in the week after Harvey struck, according to public regulatory filings aggregated by the Center for Biological Diversity.

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Hurricane Harvey has been a tornado master

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Harvey and other hurricanes have spawned tornadoes - sometimes by the dozens. And these tropical cyclones they don't need the typical recipe to spin those twisters loose.

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Hall Thruster Design Utilises Uniform Circular Motion

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Hall Thruster Design Utilises Uniform Circular Motion

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Hall Thrusters

Hall thrusters (HTs) are used in earth-orbiting satellites, and also show promise to propel robotic spacecraft long distances, such as from Earth to Mars. The propellant in a HT, usually xenon, is accelerated by an electric field which strips electrons from neutral xenon atoms, creating a plasma. Plasma ejected from the exhaust end of the thruster can deliver great speeds, typically around 70,000 mph.

Cylindrical shaped Hall thrusters (CHTs) lend themselves to miniaturization and have a smaller surface-to-volume ratio that prevents erosion of the thruster channel. Investigators at the Harbin Institute of Technology in China have developed a new inlet design for CHTs that significantly increases thrust. Simulations and experimental tests of the new design are reported this week in the journal Physics of Plasmas.

CHTs are designed for low-power operations. However, low propellant flow density can cause inadequate ionization, a key step in the creation of the plasma and the generation of thrust. In general, increasing the gas density in the discharge channel while lowering its axial velocity, i.e., the speed perpendicular to the thrust direction, will improve the thruster's performance.

Neutral Flow Dynamics

"The most practical way to alter the neutral flow dynamics in the discharge channel is by changing the gas injection method or the geometric morphology of the discharge channel," said Liqiu Wei, one of the lead authors of the paper.

The investigators tested a simple design change. The propellant is injected into the cylindrical chamber of the thruster by a number of nozzles that usually point straight in, toward the center of the cylinder. When the angle of the inlet nozzles is changed slightly, the propellant is sent into a rapid circular motion, creating a vortex in the channel.

Wei and his coworkers simulated the motion of the plasma in the channel for both nozzle angles using modeling and analysis software (COMSOL) that uses a finite element approach to modeling molecular flow. The results showed that the gas density near the periphery of the channel is higher when the nozzles are tilted and the thruster is run in vortex mode. In this mode, gas density is significantly higher and more uniform, which also helps improve thruster performance.

The investigators verified their simulation's predictions experimentally, and the vortex inlet mode successfully produced higher thrust values, especially when a low discharge voltage was used. In particular, the specific impulse of the thruster increased by 1.1 to 53.5 percent when the discharge voltage was in the range of 100 to 200 Volts.

"The work we report here only verified the practicability of this gas inlet design. We still need to study the effect of nozzle angle, diameter, the ratio of depth to diameter and the length of the discharge channel," Wei said. He went on to predict that the vortex design will be tested in flight-type HTs soon and may eventually be used in spaceflight.
This article was provided by American Institute of Physics. Materials may have been edited for clarity and brevity.

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New Thruster Design Increases Efficiency for Future Spaceflight

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Hall thrusters (HTs) are used in earth-orbiting satellites, and also show promise to propel robotic spacecraft long distances, such as from Earth to Mars. The propellant in a HT, usually xenon, is accelerated by an electric field which strips electrons from neutral xenon atoms, creating a plasma.

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Lessons from Hurricane Harvey | Opinion | Toronto Sun

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In this Monday, Aug. 28, 2017, file photo, John and Kathy Cservek hold their dogs Lacy and Iggy while being rescued from their home as floodwaters from Tropical Storm Harvey rise in Spring, Texas. The couple saw their dream house in suburban Spring devastated only a little over a year after they bought it.

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Fairground rides have been found to bring an astounding array of benefits

The novel kidney stone cure was revealed by Michigan experts last week

Can a rollercoaster's sharp ups and downs really help pass kidney stones?

For anyone who suffers from the agony of kidney stones, the news last week that riding on a rollercoaster can cure them may make a trip to the nearest theme park seem like a good idea.

In fact, these fairground thrill machines have been found to bring an astounding array of medical benefits, from easing asthma and deafness to helping one woman combat cancer.

The novel kidney stone cure was revealed by researchers at Michigan State University in the U.S.

They'd been inspired to look at this by stories of kidney stone patients who reported that riding on Walt Disney World's Big Thunder Mountain Railroad had helped them pass the troublesome growths.

One patient reported going on the ride three times and each time passing a stone afterwards.

Kidney stones occur when waste products in the blood, such as uric acid or calcium, build up into crystals that solidify into stone-like lumps.

They affect around one in six men and one in ten women - people who don't drink enough fluids are more at risk.

Most stones are small enough (less than 4mm in diameter) to be passed in urine. Larger ones can get stuck in the kidneys, causing pain and nausea. They may need to be broken up using ultrasound or laser energy.

To find out how the rollercoaster might help, the Michigan researchers rode it all day while carrying a life-size replica of the kidney of a patient who'd passed stones after the ride.

The replica kidney, made from silicone, was filled with urine and three stones.

The researchers discovered that the ride's 'rattles, sharp turns and ups and downs' dislodged the stones.

Where they sat on the ride also significantly altered the number passed, they reported in the Journal of the American Osteopathic Association.

Sitting at the back shifted the most - two-thirds, compared with under a fifth at the front.

This is possibly because the rear carriage whips over the peaks fastest, as the front carriage has already started to accelerate down the next drop.

Lead researcher David Wartinger, an emeritus professor of urology, said last week: 'My advice would be, if you have a stone capable of passage, then go to an amusement park and ride everything.'

Rollercoasters are not usually known for health benefits. Mostly, they hit the headlines following accidents, such as the crash at Alton Towers last year, in which two young women tragically lost a leg.

Moreover, researchers have generally concentrated on reports of riders injuring their necks and heads.

Doctors at the Hennepin County Medical Centre, Minneapolis, reported in the Annals of Emergency Medicine that, over a 20-year period, U.S. rollercoaster rides had been blamed for four cases of brain bruising, six burst arteries, three haemorrhages and a stroke.

Dr Jurgen Koschyk, a cardiologist at University Hospital in Mannheim, Germany, found that the intensely racing hearts the rides induce can cause arrhythmias, or irregular heartbeats, in some people, which may spur more serious issues.

Nevertheless, other reports show surprising benefits.

While riding a rollercoaster is supposed to take your breath away, Dutch psychologists have found it can do just the opposite for asthma sufferers.

They took 25 women who suffered with severe asthma on a series of rides and discovered that the euphoric thrill tended subsequently to reduce their dyspnoea - the shortness of breath characteristic of the condition.

The short-term burst of extreme physical stress appears to relax asthmatics' airways, improving their symptoms, the University of Amsterdam researchers reported in 2007 in the journal Behaviour Research and Therapy.

The sheer thrill of the ride may help, too. Adrenaline is often used as a therapeutic drug for severe asthmatics: it sets off a reaction that relaxes the muscles in the lungs' bronchial tubes, helping sufferers to breathe more easily.

With all that screaming, it seems strange to think riding a rollercoaster could rescue your hearing.

But that is just what happened to a 16-year-old schoolgirl who had become a patient at Leighton General Hospital, Crewe, in 2011.

She was referred there after becoming deaf in one ear after a holiday flight. As the plane descended, her ear had become severely muffled and painful.

The hearing loss persisted for two months, but suddenly cured itself after she rode the Rita, Queen Of Speed rollercoaster at Alton Towers.

Writing in the Indian Journal of Otolaryngology and Head & Neck Surgery, her doctors suggested the sudden change in air pressure on plummeting, combined with the extreme gravitational force, created a pulse of energy that cleared her inner ear.

Meanwhile, a theme park ride in Florida caused a British woman's brain tumour to be found early enough to be removed safely.

Sally Dare, from Tewkesbury, Gloucestershire, was on a family holiday when she went on rollercoaster The Incredible Hulk.

Afterwards, the mother-of-two complained of headaches and blurred vision.

'It was a pretty forceful ride and I was thrown about and my head was banged quite a lot,' she says. 'I felt awful afterwards, but the headaches just seemed like others I'd had, so I thought nothing of it.'

By the end of the holiday, her headaches became serious. Sally became debilitatingly dizzy, too, then found she could not remember certain words and her sight had become too blurred to read.

Her arms also started to tingle.

Back at home, Sally's GP referred her to a neurosurgeon: within days, she was diagnosed with a 2cm malignant brain tumour and it was removed.

The consultant told her that the shuddering and jolting of the ride had probably dislodged the tumour, putting pressure on parts of her brain - causing the different symptoms and leading to its early detection.

'Usually, they can go undetected until they are inoperable and the size of a tangerine,' Sally said.

'Who would have thought a holiday would trigger something like this? Going on the rollercoaster helped me. But I don't think I will ever set foot on one again.'

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Why getting on a rollercoaster can transform your life

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Fairground rides have been found to bring an astounding array of benefits The novel kidney stone cure was revealed by Michigan experts last week Can a rollercoaster's sharp ups and downs really help pass kidney stones?

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If you thought that theme parks were for children, think again. Because new research has found that there's a very adult benefit to riding rollercoasters.

Bad news for those of whose stomach lurches at the idea of stepping on a big dipper, but great news for everyone else as researchers in the US have revealed the medical benefits.

A study carried out by Michigan State University found the high speed ride could ease asthma, assist with deafness and even cure kidney stones.

Yep.

The thrilling findings come from the stories of kidney stone patients who found that a ride on Disney World's Big Thunder Mountain Railroad actually helped them pass the stones.

One even reported passing a stone after each time she rode on the giant machine.

Not content with just 'hear-say' the researchers insisted on riding the rollercoaster all day (all in the name of science) alongside a life-size replica of the patient's kidney.

They filled the false kidney with urine and three stones and found that the rigorous rattling and sharp twists and turns actually did dislodge the stones.

Lead researcher David Wartinger, an emeritus professor of urology, concluded: 'My advice would be, if you have a stone capable of passage, then go to an amusement park and ride everything.'

Well, if it comes doctor recommended...
More on Prima.co.uk... Are you better off seeing your GP in the morning? Better treatments means more of us are surviving cancer

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This is the surprising health benefit of rollercoasters

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If you thought that theme parks were for children, think again. Because new research has found that there's a very adult benefit to riding rollercoasters. Bad news for those of whose stomach lurches at the idea of stepping on a big dipper, but great news for everyone else as researchers in the US have revealed the medical benefits.

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But one particular gentleman really inspired Wartinger. The man rode Big Thunder Mountain Railroad at Disney's Magic Kingdom, and then passed a small stone. Then he did it again and passed another. And then another. "That was just too powerful to ignore," Wartinger said. "I'd been hearing these anecdotal stories for a couple years, and then I thought, okay, there's really something here."

If there were a way to make people pass stones while they were still small, Wartinger realized, the potential benefits could be enormous.

So Wartinger compiled people's stories, and he realized that the common factor was having ridden Big Thunder Mountain Railroad. He found anecdotal reports of people passing stones after bungee jumping, but no research on this bodily-movement approach. So he decided to take things into his own hands and do a proper study.

First, Wartinger used a 3-D printer to create a clear silicone model of that three-time-stone patient's kidney. He then filled the kidney with stones and urine. (Not real urine, I assumed, as I know the park already has plenty.) Then he and colleague Marc Mitchell bought two tickets and flew to Orlando.

Of course, the researchers had to get permission from Disney World before bringing the model kidney onto the rides. "It was a little bit of luck," Wartinger recalls. "We went to guest services, and we didn't want them to wonder what was going on-two adult men riding the same ride again and again, carrying a backpack. We told them what our intent was, and it turned out that the manager that day was a guy who recently had a kidney stone. He called the ride manager and said, do whatever you can to help these guys, they're trying to help people with kidney stones."

There are other kidney designs to consider, too, as every person's calyceal system is different, like a fingerprint. But the idea is that if you rode a variety of roller coasters in a short period of time, that would help you pass small stones and lingering sediment before it accumulates into debilitating, costly, obstructive stones.

Still to know if this works for sure, he'd need a prospective clinical trial using real people with real kidneys. I suggested that would be difficult. He said no, he has it all planned out: Take people with kidney stones and do an ultrasound before the ride and after, and see if the stone moves. Wartinger couldn't do that right away because universities' institutional review boards would require experimental evidence to prove the concept first.

This he seems to have done duly on Big Thunder Mountain Railroad, with attention to detail. For example, I thought I was just clarifying one such detail when I asked if the "urine" described in the model he brought to Disney was actually water. It was water, right?

"No, it was urine. It was mine."

I still wasn't sure if he was serious. I have no problem with urine, it's just the idea of showing up at Disney with a urine-loaded kidney in your backpack.

"Yeah, I used dilute urine. I spent my life playing in pee. I don't have that aversion to urine that most people have. The reason I didn't use water is it would've put another variable in there that wasn't real. So I used real urine ... to avoid criticism."

It seems he thought of everything. Including the fact that people will hear about this study and act on it before it's validated in human trials. So his advice for now: If you know you have a stone that's smaller than five millimeters, riding a series of roller coasters could help you pass that stone before it gets to an obstructive size and either causes debilitating colic or requires a $10,000 procedure to try and break it up. And even once a stone is broken up using shock waves, tiny fragments and "dust" remain that need to be passed. The coaster could help with that, too.

For people who hate roller coasters, like a number of people I've run this idea by, the ultimate goal would be a more clinical experience-a way to move people in a controlled environment that would help them pass stones organically. Instead of sending people to a theme park, you might go down the hall to a 3-D rollercoaster with a prescription for a precise pattern of pitches, yaws, and rolls designed around your particular kidney anatomy and the location of your particular stone.

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Stones Have Been Popping Out of People Who Ride Roller Coasters

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But one particular gentleman really inspired Wartinger. The man rode Big Thunder Mountain Railroad at Disney's Magic Kingdom, and then passed a small stone. Then he did it again and passed another. And then another. "That was just too powerful to ignore," Wartinger said.

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Source: http://www.flickr.com/photos/celesteh/3266073975

Ferris wheel physics is directly related to centripetal acceleration, which results in the riders feeling "heavier" or "lighter" depending on their position on the Ferris wheel.

The Ferris wheel consists of an upright wheel with passenger gondolas (seats) attached to the rim. These gondolas can freely pivot at the support where they are connected to the Ferris wheel. As a result, the gondolas always hang downwards at all times as the Ferris wheel spins.

To analyze the Ferris wheel physics, we must first simplify the problem. The figure below shows a schematic of the Ferris wheel, illustrating the essentials of the problem.

Where:

(1) is the top-most position and (2) is the bottom-most position

Point P is where the gondolas are attached to the Ferris wheel

Point C is where the passengers sit (on the gondola)

R is the radius of the Ferris wheel

w is the angular velocity of the Ferris wheel, in radians/s

The forces acting on the passengers are due to the combined effect of gravity and centripetal acceleration, caused by the rotation of the Ferris wheel with angular velocity w.

We wish to analyze the forces acting on the passengers at locations (1) and (2). The figure below shows a free-body diagram for the passengers at these locations.

Where:

mg is the force of gravity pulling down on the passengers, where m is the mass of the passengers and g is the acceleration due to gravity, which is 9.8 m/s ²

is the force exerted on the passengers (by the seats) at point C, at location (1)

is the force exerted on the passengers (by the seats) at point C, at location (2)

is the centripetal acceleration of point P. This acceleration is always pointing towards the center of the wheel. So at location (1) this acceleration is pointing directly down, and at location (2) this acceleration is pointing directly up.

The centripetal acceleration is given by

The centripetal acceleration always points towards the center of the circle. So at the bottom of the circle, is pointing up. At the top of the circle is pointing down. At these two positions is a vector which is aligned (parallel) with gravity, so their contributions can be directly added together.

By Newton's second law

where Σ F is the sum of the forces.

To solve for and we must apply this equation in the vertical direction.

The acceleration of the passengers at point C is equal to the acceleration of the Ferris wheel at point P. This is because point C does not move relative to point P. Therefore, the velocity and acceleration of these two points are the same.

First, solve for N₁

Next, solve for N₂

We can see that > . This means that the passengers feel "heaviest" at the bottom of the Ferris wheel, and the "lightest" at the top.

So basically, the motion of a Ferris wheel affects your bodies "apparent" weight, which varies depending on where you are on the ride. The riders only feel their "true weight", when the centripetal acceleration is pointing horizontally and has no vector component parallel with gravity, and as a result it has no contribution in the vertical direction. This occurs when the riders are exactly halfway between the top and bottom (i.e. they are at the same height as the center of the Ferris wheel).

It's informative to look at an example to get an idea of how much force acts on the passengers.

Let's say we have a Ferris wheel with a radius of 50 meters, which makes two full revolutions per minute.

Two full revolutions per minute translates into w = 0.21 radians/s.

Substituting this into the above equations we find that

= 2.2 m/s ² (centripetal acceleration)

Therefore,

At the top of the Ferris wheel the passengers experience 0.78 g (they feel lighter).

At the bottom of the Ferris wheel the passengers experience 1.2 g (they feel heavier).

Now that we understand the physics of a Ferris wheel, one can imagine how important it is for a large radius Ferris wheel to turn slowly, given how much influence the rotation rate w will have on the centripetal acceleration , and on and , as a result.

Return to Amusement Park Physics page

Return to Real World Physics Problems home page

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Source: http://www.flickr.com/photos/celesteh/3266073975 Ferris wheel physics is directly related to centripetal acceleration, which results in the riders feeling "heavier" or "lighter" depending on their position on the Ferris wheel. The Ferris wheel consists of an upright wheel with passenger gondolas (seats) attached to the rim.

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The giant, futuristic structure in Weifang City, China, comes with 36 carts able to carry 10 passengers each

It has been built onto the 1,771ft Bailang River Bridge - hence the name Bailang River Bridge Ferris Wheel

Each carriage has its own television, which it's thought will play real-time footage of the passengers' location

An incredible new spokeless Ferris Wheel will soon open to the public in China - complete with built-in television sets and even wireless internet for all the inevitable selfies.

The giant, futuristic structure comes with 36 carts able to carry 10 passengers each, all of whom will be offered an unparalleled view of the Bailang River in Weifang City, in East China's Shandong Province.

It has been built onto the 1,771ft Bailang River Bridge - hence the name Bailang River Bridge Ferris Wheel - and it is now ready to roll.

Scroll down for video

As the world's first spokeless Ferris wheel with grid design, the 475ft tall amusement park-style attraction is set to become Weifang's newest and most eye-catching landmark.

Perhaps most surprising of all is that engineers have felt the need to install television sets inside the carts.

The designers have yet to reveal what will be played on the TVs, but members of the public have guessed it could be real-time footage of their location in relation to the whole wheel.

WiFi will also be offered in each cart, allowing tourists to connect to the internet with their mobile devices and brag to the world about their experiences right away.

Some 4,600 tonnes of steel were used in the building of the Ferris wheel, which will take exactly 28 minutes to complete one rotation - plenty of time for tourists to snap up some amazing photos.

The crisscrossing steel beams holding the Ferris wheel together have been described as a 'dragon spine', and the complex architecture is vital for pulling off the spokeless and shaftless design, making the centre completely hollow like a giant high-tech wheel.

Weifang City plans to begin trialing the Ferris Wheel in time for the May Day holidays in the beginning of next month.

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Amazing new spokeless Ferris Wheel opens in China

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The giant, futuristic structure in Weifang City, China, comes with 36 carts able to carry 10 passengers each It has been built onto the 1,771ft Bailang River Bridge - hence the name Bailang River Bridge Ferris Wheel Each carriage has its own television, which it's thought will play real-time footage of the passengers' location An incredible new spokeless Ferris Wheel will soon open to the public in China - complete with built-in television sets and even wireless internet for all the inevitable selfies.

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A DEADLY ride malfunction has left one man dead and seven more injured - several critically - at the Ohio State Fair in Columbus, USA.

The swinging and spinning amusement park ride called the Fire Ball broke apart on the opening day of the Ohio State Fair on Wednesday, hurling people through the air. Bystanders said they heard metal cracking as the ride broke apart.

Ohio's governor Republican Gov. John Kasich is calling it "a terrible, terrible tragedy."

Dramatic video captured by a bystander and circulating on social media shows the ride swinging back and forth like a pendulum and spinning in the air before it crashed and part of the ride flew off, throwing riders to the ground with it.

In the video, a row of seats appears to snap off the ride as it begins to swing up.

Some passengers appear hit the ground with the seat section, while at least two others are hurled through the air.

The victims range in age between 13 and 41 years old, with the Columbus Dispatch saying the dead man was 18 years old.

Battalion Chief Steve Martin, a spokesman for the Columbus Fire Division, said some of the victims were thrown from the Fire Ball ride during the incident at approximately 7.20pm.

One man was thrown high into the air and landed on the ground about 15 metres from the ride, Martin said. He was killed on impact.

Three other people - including another person seen flying from the ride - were in critical condition and four more were in stable condition, authorities said on Wednesday night..
"AGGRESSIVE THRILL RIDE"
A company providing rides at the fair this year describes the Fire Ball as an "aggressive thrill" ride.

Kasich has ordered a full investigation and ordered that all fair rides be shut down until additional safety inspections can be completed.

Kasich said before this happened, he always thought of the fair, which opened Wednesday, as one of "the best things in life."

In a statement posted on its Twitter page, the fair says it is investigating. It did not immediately respond to a request seeking further comment.

On its website, Amusements of America says that since its debut in 2002, the Fire Ball has become "one of the most popular thrill rides on the AOA Midway."

The company description of the ride says it swings riders 12 metres above the midway, while spinning them at 13 revolutions per minute. The company did not immediately return a phone message seeking comment.
RIDE PASSED INSPECTIONS
The Fire Ball ride had passed pre-fair inspections, officials said.

Director of Agriculture David Daniels said all of the rides are checked several times when they are being set up to ensure they are set up the way the manufacturer intended.

"We started out today with 11 rides that did not open because the inspection work was not done on them," said Daniels, adding that four rides will not be operating because they do not meet the mechanical test.

Ride inspectors said the Fire Ball ride was inspected at a couple of different stages and was signed off on Wednesday.

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A DEADLY ride malfunction has left one man dead and seven more injured - several critically - at the Ohio State Fair in Columbus, USA. The swinging and spinning amusement park ride called the Fire Ball broke apart on the opening day of the Ohio State Fair on Wednesday, hurling people through the air.

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Bullet was fired from a McMillan TAC-50 rifle set up on a high-rise tower in Iraq

The sniper disrupted an ISIS fighter who was attacking a group of Iraqi soldiers

Smashes record set by British soldier Craig Harrison, who hit target at 1.54 miles

A Canadian sniper has beat the record for the longest confirmed kill in military history by picking off an ISIS fighter from a staggering 11,319 feet.

Major-General Michael Rouleau said the troops, whose job it is to advise and assist the Iraqi security forces, fired in defence of their partner.

The bullet was fired from a McMillan TAC-50 rifle set on a high-rise tower and took 10 seconds to travel the 2.14 miles towards the fighter, who was attacking Iraqi soldiers.

This smashed the last record set by a Briton Craig Harrison, who killed a Taliban soldier with a 338 Lapua Magnum rifle at a range of 8,120 feet(1.54 miles) in 2009.

A military source told The Globe and Mail the kill was verified by video, adding: 'This is an incredible feat. It is a world record that might never be equalled.'

The third longest kill was by Canadian Corporal Rob Furlong, who shot down an Afghan insurgent from 7,972 feet(1.51 miles) in 2002 during Operation Anaconda.

And prior to that, Master Corporal Arron Perry hit a terrorist from 7579 feet. He was also Canadian and serving in the same operation.

The longest kill from a US sniper was done by sergeant Bryan Kremer, who hit an Iraqi insurgent at 7,546 feet(1.42 miles) with his Barrett M82A1 rifle in 2004.

The Canadian who achieved the longest kill was operating with Joint Task Force 2, which is training Kurdish forces to fight IS.

Few details are available about their operation, but their last reported location was in the north of Iraq, where a major operation is underway to recapture Mosul.

The sniper has not been named for security reasons and the exact location of the kill has not been confirmed.

Canada's special forces are known for the high skill of their snipers, who are considered among the best in the world.

They have been fighting in the Middle East for several years, and were involved in the first confirmed ground battle between ISIS and western forces in January 2015.

Soldiers visiting front-line positions with Kurdish Peshmerga forces came under heavy mortar and machine gun fire.

McMillan Tac-50: Killing machine with lethal range of 2.3miles

The Canadians used sniper fire to 'neutralise' the ISIS threat without taking any casualties.

Major-General Michael Rouleau said the troops, whose job it is to train the Iraqi military, fired back only in self-defence.

Special forces fighting in Iraq and Syria regularly make use of sniper rifles, as they are considered a more accurate way of targeting insurgents than airstrikes.

Last month, a British SAS sniper is said to have shot dead an ISIS jihadi from 7,920 feet (1.50 miles) away using the world's most powerful rifle.

The kill was unconfirmed by the military so is not included in the league table.

It took three whole seconds for the bullet to reach its target - the throat of an Islamic State terrorist in the Iraqi city of Mosul.

The British marksman was using a CheyTac M200 Intervention gun which is produced in South Carolina and retails at $13,800 (£10,500) and can vaporise a person's organs from 8,200 feet.

As the terrorist was leaving a burned-out building two weeks ago, the SAS gunman is said to have pulled the trigger, registering one of the most difficult kills in the regiment's history.

Widely regarded as the most powerful rifle on the planet in its class, it has a working range of up to 9,842 feet and holds the record for the world's longest shot.

The soldiers is said to have only taken a single shot to take down his man, living up to the gun manufacturer CheyTac's motto of 'Make every shot count'.

A source told The Star on Sunday: 'It was a classic counter-sniper operation. The ISIS gunman was moving all the time to get into the best position to get a kill.'

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Canadian sniper kills an ISIS fighter from TWO MILES away

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Bullet was fired from a McMillan TAC-50 rifle set up on a high-rise tower in Iraq The sniper disrupted an ISIS fighter who was attacking a group of Iraqi soldiers Smashes record set by British soldier Craig Harrison, who hit target at 1.54 miles A Canadian sniper has beat the record for the longest confirmed kill in military history by picking off an ISIS fighter from a staggering 11,319 feet.

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Chase Elliott's car lifted off the ground and AJ Allmendinger's car completely flipped over in an accident that involved 18 drivers during Sunday's NASCAR Monster Energy Cup Series race at Talladega Superspeedway.

Allmendinger was running third and directly behind Elliott when he tapped Elliott's left-rear bumper, which turned the No. 24 car sideways and left Allmendinger with no means to avoid further contact. Elliott's car got airborne before settling back on all four wheels, while Allmendinger's No. 47 Chevrolet flipped on its roof.

"I barely tapped him," Allmendinger said. "And then I tried to get off him but at that point it was too late. It was just one of those things battling for the lead."

The accident occurred on the backstretch with 20 regulation laps remaining in the Geico 500. (The race would go into overtime due to a late caution.) NASCAR red flagged the race for nearly 27 minutes to remove the wreckage and clean away the debris.

"I don't know that it was really (Allmendinger's) fault, per se," Elliott said. "He had a big run and he kind of got to my bumper and just happened to be in a bad spot coming up off the corner and was skewed a little bit to my left rear. And when that happens, it just unloads these cars too much."

Among those collected in the wreck were contenders Joey Logano, Kevin Harvick, Brad Keselowski, Matt Kenseth, Martin Truex Jr., Kurt Busch, and Trevor Bayne. After making repairs, Busch and Keselowski were able to continue and rallied to finish sixth and seventh, respectively.

Despite multi-car accidents being synonymous with racing at Talladega, one of two restrictor-plate tracks on the Cup schedule, this was the only "big one" on the afternoon.

"Got in a bad spot and then they started wrecking," Truex said. "It's a shame, it's the way it goes here."

Because of limited horsepower, races at Talladega and Daytona International Speedway see drivers largely unable to separate from one another. Large packs of cars then form, often resulting in accidents like the one that occurred on Sunday.

"It's Talladega," Allmendinger said. "I'm not a big fan of it, but if you're up front and you've got a chance to go for it, racing happens I guess, here."

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18-car accident sees AJ Allmendinger flip during NASCAR race at Talladega

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Chase Elliott's car lifted off the ground and AJ Allmendinger's car completely flipped over in an accident that involved 18 drivers during Sunday's NASCAR Monster Energy Cup Series race at Talladega Superspeedway. Allmendinger was running third and directly behind Elliott when he tapped Elliott's left-rear bumper, which turned the No.

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Australian stunt crew break world record for longest basketball shot

In a mega-dam in Switzerland they shot a basket at 180 metres tall

The crew, How Ridiculous, will be looking to further their own feat

An Australian stunt crew have broken an incredible world record by netting a basketball shot from 180m in just three shots.

The highly coveted world record for the longest basketball shot has been intensely battled over the last year, but Youtube sensations How Ridiculous have reclaimed their old title.

Brett, Scott and Derek from Perth began performing trick shots in their backyard but held the world record after sinking an incredible 126 metre basket last year at a dam in Tasmania.

The record went global with more than five million views on Youtube in the first week.

However, tricksters Dude Perfect from the U.S. lived up to their name sake and broke the world record by 36 metres in Oklahoma.

'I mean they're very much like us, they love to push the limits they love to try and do things that people haven't done so ...I'm sure they would have seen it and been like alright if we get the chance we'd love to try and top that,' Brett Stanford told Sevens Sunday Night.

In a bid to regain their title, How Ridiculous ended up in Switzerland at a mega-dam standing at a whopping 180 metres tall.

Expecting to spend up to five days at the dam trying to sink a seemingly impossible shot, Derek lined up at the top of the dam and sunk the world record in just three attempts.

Derek said after his first two attempts he wasn't far off and he just let it go.

'Then all of a sudden it's like, I see this net move,' Derek said.

'Then I see Scott at the bottom I see his arms go up and then I just knew from that point that was it we'd done it and third attempt it was just mind blowing really.'

The team had even impressed themselves.

'No one should expect to go do that in less than a couple of days, you know, and yet it took Derek a couple of throws!', the team said.

Unbelievably the three world record holders from Perth are not waiting for their rival tricksters to outdo them, but will be looking to break their own jaw-dropping feat.

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Australian crew break record for highest basketball shot

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Australian stunt crew break world record for longest basketball shot In a mega-dam in Switzerland they shot a basket at 180 metres tall The crew, How Ridiculous, will be looking to further their own feat An Australian stunt crew have broken an incredible world record by netting a basketball shot from 180m in just three shots.

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India will collaborate with Switzerland for developing trains which will tilt on approaching a bend, just like a motorbike on a winding road.

A memorandum of understanding was signed on Thursday between the two countries in this regard.

Such trains are now operational in 11 countries -- Italy, Portugal, Slovenia, Finland, Russia, the Czech Republic, the UK, Switzerland, China, Germany and Romania.

Explaining how the tilting trains work, officials said that as a train rounds a curve at speed it causes objects to slide about.

"While it makes seated passengers feel squashed by the armrest, standing passengers tend to lose their balance. The design of the tilting trains counteract this," an official said.

During a curve to the left, the train tilts to the left and vice versa, the official said.

The railway ministry signed two MoUs with the Federal Department of the Environment, Transport and Communications of the Swiss Confederation for technical cooperation in rail sector in the presence of Prime Minister Narendra Modi.

The first agreement is a follow up on bilateral cooperation in rail sector discussed in the meeting held between Railway Minister Suresh Prabhu and the Swiss Ambassador in July 2016.

The MoU aims at cooperation in the areas of traction rolling stock, electric multiple unit and train sets, traction propulsion equipments, freight and passenger cars, tilting trains, railway electrification equipments, tunnelling technology among other things.

The second MoU was signed between Konkan Railway Corporation Limited (KRCL) and Swiss Federal Institute of Technology which will help the former in establishing the George Fernandes Institute of Tunnel Technology (GFITT) at Goa especially for assimilation and dissemination of knowledge in the field of tunnelling, the officials said.

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Swiss-Style Tilting Trains Soon To Hit Tracks In India

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India will collaborate with Switzerland for developing trains which will tilt on approaching a bend, just like a motorbike on a winding road. A memorandum of understanding was signed on Thursday between the two countries in this regard. Such trains are now operational in 11 countries -- Italy, Portugal, Slovenia, Finland, Russia, the Czech Republic, the UK, Switzerland, China, Germany and Romania.