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Hot air balloons work because hot air rises. By heating the air inside the balloon with the burner, it becomes lighter than the cooler air on the outside. This causes the balloon to float upwards as if it were in the water. Obviously, if the air is allowed to cool, the balloon begins to slowly come down.

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Hot air balloons work because hot air rises. By heating the air inside the balloon with the burner, it becomes lighter than the cooler air on the outside. This causes the balloon to float upwards as if it were in the water. Obviously, if the air is allowed to cool, the balloon begins to slowly come down.

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By Kin pls add something

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As heat is applied to the dried kernels, the droplet of water converts to steam, and pressure begins to build. Once the hull can no longer hold the pressure of the steam, the kernel explodes. The starch inside the kernel turns into the white fluffy, crunchy stuff we call popcorn.  Popcorn is actually a special variety of corn, and it is the only one that pops. The key to popcorn is the unique design of its kernels. Most importantly, its kernel consists of a very hard, mostly nonporous outer shell called pericarp.  In some forms of popcorn, the corn itself is the only raw material. For other methods of marketing popcorn such as microwave popcorn, soybean oil, salt, and flavoring are also needed.  The popcorn at the movies isn't made with butter at all. The corn kernels are cooked in coconut or canola oil and sprinkled with a concoction of salt, butter flavorings, and bright-yellow food coloring. In reality, most major theaters pop their kernels in coconut oil (via The New York Times), adding flavours as it pops to imbue the fluffy popped kernels with that signature yellow color and salty taste (via Extra Crispy).

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As heat is applied to the dried kernels, the droplet of water converts to steam, and pressure begins to build. Once the hull can no longer hold the pressure of the steam, the kernel explodes. The starch inside the kernel turns into the white fluffy, crunchy stuff we call popcorn.  Popcorn is actually a special variety of corn, and it is the only one that pops. The key to popcorn is the unique design of its kernels. Most importantly, its kernel consists of a very hard, mostly nonporous outer shell called pericarp.  In some forms of popcorn, the corn itself is the only raw material. For other methods of marketing popcorn such as microwave popcorn, soybean oil, salt, and flavoring are also needed.  The popcorn at the movies isn't made with butter at all. The corn kernels are cooked in coconut or canola oil and sprinkled with a concoction of salt, butter flavorings, and bright-yellow food coloring. In reality, most major theaters pop their kernels in coconut oil (via The New York Times), adding flavours as it pops to imbue the fluffy popped kernels with that signature yellow color and salty taste (via Extra Crispy).

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I-yah

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Popcorn is a variety of corn kernel which expands and puffs up when heated

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Popcorn is a variety of corn kernel which expands and puffs up when heated

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hana

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By : VIVI P4 CONFIDENCE 😁                                  Why do power lines hung slack?                              The lines are often heavily loaded because of increased power consumption, and the conductors, which are generally made of copper or aluminum, expand when heated. That expansion increases the slack between transmission line structures, causing them to sag. 

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By : VIVI P4 CONFIDENCE 😁                                  Why do power lines hung slack?                              The lines are often heavily loaded because of increased power consumption, and the conductors, which are generally made of copper or aluminum, expand when heated. That expansion increases the slack between transmission line structures, causing them to sag. 

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Hot air balloons are based on a very basic scientific principle: warmer air rises in cooler air. Essentially, hot air is lighter than cool air, because it has less mass per unit of volume. .Therefore, each cubic foot of air contained in a hot air balloon can lift about 7 grams.

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By Faye

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How Do Hot Air Balloons Work? | Best Learning Videos For Kids | Thinking Captain

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Power Lines are hung slack because, the lines are heavily loaded because of the amount of power in each Power Line,  and the conductors, which are generally made of copper or aluminum, expand when heated. That expansion increases the slack between transmission line structures, causing them to sag. By Poy

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To keep the balloon rising, you need a way to reheat the air. Hot air balloons do this with a burner positioned under an open balloon envelope. As the air in the balloon cools, the pilot can reheat it by firing the burner.Modern hot air balloons heat the air by burning propane, the same substance commonly used in outdoor cooking grills. The propane is stored in compressed liquid form, in lightweight cylinders positioned in the balloon basket. The intake hose runs down to the bottom of the cylinder, so it can draw the liquid out.Because the propane is highly compressed in the cylinders, it flows quickly through the hoses to the heating coil. The heating coil is simply a length of steel tubing arranged in a coil around the burner. When the balloonist starts up the burner, the propane flows out in liquid form and is ignited by a pilot light. As the flame burns, it heats up the metal in the surrounding tubing. When the tubing becomes hot, it heats the propane flowing through it. This changes the propane from a liquid to a gas, before it is ignited. This gas makes for a more powerful flame and more efficient fuel consumption.In most modern hot air balloons, the envelope is constructed from long nylon gores, reinforced with sewn-in webbing. The gores, which extend from the base of the envelope to the crown, are made up of a number of smaller panels. Nylon works very well in balloons because it is lightweight, but it is also fairly sturdy and has a high melting temperature. The skirt, the nylon at the base of the envelope, is coated with special fire-resistant material, to keep the flame from igniting the balloon.

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To keep the balloon rising, you need a way to reheat the air. Hot air balloons do this with a burner positioned under an open balloon envelope. As the air in the balloon cools, the pilot can reheat it by firing the burner.Modern hot air balloons heat the air by burning propane, the same substance commonly used in outdoor cooking grills. The propane is stored in compressed liquid form, in lightweight cylinders positioned in the balloon basket. The intake hose runs down to the bottom of the cylinder, so it can draw the liquid out.Because the propane is highly compressed in the cylinders, it flows quickly through the hoses to the heating coil. The heating coil is simply a length of steel tubing arranged in a coil around the burner. When the balloonist starts up the burner, the propane flows out in liquid form and is ignited by a pilot light. As the flame burns, it heats up the metal in the surrounding tubing. When the tubing becomes hot, it heats the propane flowing through it. This changes the propane from a liquid to a gas, before it is ignited. This gas makes for a more powerful flame and more efficient fuel consumption.In most modern hot air balloons, the envelope is constructed from long nylon gores, reinforced with sewn-in webbing. The gores, which extend from the base of the envelope to the crown, are made up of a number of smaller panels. Nylon works very well in balloons because it is lightweight, but it is also fairly sturdy and has a high melting temperature. The skirt, the nylon at the base of the envelope, is coated with special fire-resistant material, to keep the flame from igniting the balloon.

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By Kin

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The basic principle behind hot air balloon physics is the use of hot air to create buoyancy, which generates lift. A hot air balloon consists of a large bag, called an envelope, with a gondola or wicker basket suspended underneath. ... This heated air generates lift by way of a buoyant force.

By Jay =) =) =) =) =)

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Hot Air Balloon- Fall Color- Prep, Take Off, Flight, Landing

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The kernels of the corn gets heated and when they can't hold they explode and expand. Paopao

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By Kin :)

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How Do Hot Air Balloons Work? | Best Learning Videos For Kids | Thinking Captain

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During transmission of electricity, heat is being dissipated. The heat generated by cables is being minimized via high voltage transmission. ... So, the cables are loose so that even if contraction should occur, there won't be much tension which would lead to the damage of the cables.by nauny

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­If you actually need to get somewhere, a hot air balloon is a fairly impractical vehicle.You can't really steer it, ­and it only travels as fast as the wind blows. But if you simply want to enjoy the experience of flying, there's nothing quite like it. Many people describe flying in a hot air ballo­on as one of the most serene, enjoyable activities they've ever experienced.­Hot air balloons are also an ingenious application of basic scientific principles. In this article, we'll see what makes these balloons rise up in the air, and we'll also find out how the balloon's design lets the pilot control altitude and vertical speed. You'll be amazed by the beautiful simplicity of these early flying

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­If you actually need to get somewhere, a hot air balloon is a fairly impractical vehicle.You can't really steer it, ­and it only travels as fast as the wind blows. But if you simply want to enjoy the experience of flying, there's nothing quite like it. Many people describe flying in a hot air ballo­on as one of the most serene, enjoyable activities they've ever experienced.­Hot air balloons are also an ingenious application of basic scientific principles. In this article, we'll see what makes these balloons rise up in the air, and we'll also find out how the balloon's design lets the pilot control altitude and vertical speed. You'll be amazed by the beautiful simplicity of these early flying

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The wheels on each side of a train car are connected with a metal rod called an axle. This axle keeps the two train wheels moving together, both turning at the same speed when the train is moving. ... This is where the wheels' geometry comes in. To help the wheels stay on the track their shape is usually slightly conical
By Jay =)

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The hot air balloon is consists of three main parts.

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The hot air balloon is consists of three main parts.

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Special kernels are selected from special corn,and then dried to at least 15% of water.Heat gelatinizes in the starch and vaporizes water in the kernel and creating pressure.Pressure builds up and burst the hull release a protein foam that cools and becomes fluffy popcorn

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By:Kin

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The gaps left between successive rails on a railway track, the reason is that the rails expand in summer. The gap is provided to allow for this expansion. If no gap is left, the expansion in summer will cause the rails to bend sideways. That will result in train accidents.  The distance between the two tracks in this railway gauge is 1435 mm (4 ft 8½ in). In India, standard gauge is used only for urban rail transit systems like Metro, Monorail and Tram. Track ballast forms the track bed upon which railroad ties (sleepers) are laid. It is packed between, below, and around the ties. It is used to bear the load from the railroad ties, to facilitate drainage of water, and also to keep down vegetation that might interfere with the track structure.

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The gaps left between successive rails on a railway track, the reason is that the rails expand in summer. The gap is provided to allow for this expansion. If no gap is left, the expansion in summer will cause the rails to bend sideways. That will result in train accidents.  The distance between the two tracks in this railway gauge is 1435 mm (4 ft 8½ in). In India, standard gauge is used only for urban rail transit systems like Metro, Monorail and Tram. Track ballast forms the track bed upon which railroad ties (sleepers) are laid. It is packed between, below, and around the ties. It is used to bear the load from the railroad ties, to facilitate drainage of water, and also to keep down vegetation that might interfere with the track structure.

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I-yah

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Hot air balloons are based on a very basic scientific principle: warmer air rises in cooler air. Essentially, hot air is lighter than cool air, because it has less mass per unit of volume. A cubic foot of air weighs roughly 28 grams (about an ounce). If you heat that air by 100 degrees F, it weighs about 7 grams less. Therefore, each cubic foot of air contained in a hot air balloon can lift about 7 grams. That's not much, and this is why hot air balloons are so huge -- to lift 1,000 pounds, you need about 65,000 cubic feet of hot air.

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By:Kin pls watch

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How Do Hot Air Balloons Work? | Best Learning Videos For Kids | Thinking Captain

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by mark

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Why does hot air balloon float? | #aumsum #kids #science #education #children

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This is how it work
It have line to make it work together. There are heavily because loaded because of the amount of power to each Power line. The power of line have to be strong to lend signal

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Keep it up guys!

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By Noodee

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Charles's Law says that the volume of a gas is directly related to the temperature of that gas, similarly when a gas is heated, like a burner in a hot air balloon, the gas expands. So when the air inside the balloon expands, it becomes less dense and provides the lift for the hot air balloon

By Jay =) =) =)

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Why does hot weather make railways bend?Image may contain Transportation Train Track Railway Rail and ConstructionRail tracks outside London Paddington during an August 2003 heatwave. Network Rail imposed speed restrictions on some lines as temperatures passed 35CBRUNO VINCENT/GETTY IMAGESTemperatures in south-east England are set to hit 31C today, causing a strange problem for the UK's railways: bending rails. But how can a warm summer day potentially bring the UK's trains to a standstill?Rails are made of steel which expands as it heats up. If trains go too fast they risk buckling the track. While the air temperature might be 31C, temperatures on tracks can exceed 50C during heatwaves.Just a few hours of above-average heat is enough to cause problems. Today's hot weather has caused First Great Western to impose speed restrictions and alter some services in the Thames Valley until 8pm.Blanket speed restrictions, which prevent trains from slowing down and speeding up excessively, are the best way to prevent buckling in hot conditions. Both the heat and the train passing over a rail can cause it to buckle, which is why in some instances trains may be cancelled altogether.To stop this from happening hydraulic machines are used to artificially stretch rails as they are placed. This stretching means that even if the rails heat up they won't expand, but once temperatures go beyond 30C overheating becomes an issue.There's also a limit to how much a rail can be stretched -- take it too far and you risk rails cracking during cold winters. How much a rail is stretched is therefore a careful balancing act.The problem can also be exacerbated by the poor condition of a rail line. If the gravel used to lay rails and sleepers has fallen away tracks tend to wobble, which can worsen the impact of buckling. Newer lines, laid with better fastenings and sensors to detect potential problems, are less prone to buckling.While the amount of expansion is relatively minor, when expanded to mile upon mile of welded steel it becomes significant. As modern tracks are welded together into continuous lines to create a smoother ride this small expansion is amplified. On straight tracks the buckle is typically "S" shaped, on corners you normally get a "C" shaped buckle.High-quality ballast, sensors and regular monitoring of rail conditions during both extreme hot and cold weather should all ensure a hassle-free ride for passengers, but hot weather continues to cause problems for the UK's railways.

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Why does hot weather make railways bend?Image may contain Transportation Train Track Railway Rail and ConstructionRail tracks outside London Paddington during an August 2003 heatwave. Network Rail imposed speed restrictions on some lines as temperatures passed 35CBRUNO VINCENT/GETTY IMAGESTemperatures in south-east England are set to hit 31C today, causing a strange problem for the UK's railways: bending rails. But how can a warm summer day potentially bring the UK's trains to a standstill?Rails are made of steel which expands as it heats up. If trains go too fast they risk buckling the track. While the air temperature might be 31C, temperatures on tracks can exceed 50C during heatwaves.Just a few hours of above-average heat is enough to cause problems. Today's hot weather has caused First Great Western to impose speed restrictions and alter some services in the Thames Valley until 8pm.Blanket speed restrictions, which prevent trains from slowing down and speeding up excessively, are the best way to prevent buckling in hot conditions. Both the heat and the train passing over a rail can cause it to buckle, which is why in some instances trains may be cancelled altogether.To stop this from happening hydraulic machines are used to artificially stretch rails as they are placed. This stretching means that even if the rails heat up they won't expand, but once temperatures go beyond 30C overheating becomes an issue.There's also a limit to how much a rail can be stretched -- take it too far and you risk rails cracking during cold winters. How much a rail is stretched is therefore a careful balancing act.The problem can also be exacerbated by the poor condition of a rail line. If the gravel used to lay rails and sleepers has fallen away tracks tend to wobble, which can worsen the impact of buckling. Newer lines, laid with better fastenings and sensors to detect potential problems, are less prone to buckling.While the amount of expansion is relatively minor, when expanded to mile upon mile of welded steel it becomes significant. As modern tracks are welded together into continuous lines to create a smoother ride this small expansion is amplified. On straight tracks the buckle is typically "S" shaped, on corners you normally get a "C" shaped buckle.High-quality ballast, sensors and regular monitoring of rail conditions during both extreme hot and cold weather should all ensure a hassle-free ride for passengers, but hot weather continues to cause problems for the UK's railways.

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By Kin

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By:Kin pls watch

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How Do Hot Air Balloons Work? | Best Learning Videos For Kids | Thinking Captain

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We can notice that there are gaps in the train tracks because the rails expand on summer. The rails expand on summer because of the devastating heat that it gives on summer. The gap is provided to allow for this expansion. If no gap is provided, the expansion in summer will cause the rails to bend sideways. Wich will result in train accidents.

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railway tracks have gaps because with all the presure it needs air to move and also to make sure it dont have too much heat in the rail way for the fact the train dont move by humans,they have magnets to move and will not top till landed to there destination.The sides of the railway are there because it will keep the train steady and the train will not fall. alice

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Because the gaps helps the train not to bend on the rail tracks, normally, the tracks are made of steel so in summer, the sun will expand heat to the rail way and the rail way will expand so the train bends to the right and crash, but with the gaps, the rail tracks doesn’t attract to each other a little metal bar attracts both of the rail tracks so it doesn’t bend
-by Alan