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list sources of radiation in your physics class

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list sources of radiation in your physics class

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1. Reducing exposure time                                                                    2.increasing the distance between the source and living tissue                                                                                  3.using shielding ( LEAD -BOXES) to absorb radiation

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1. Reducing exposure time                                                                    2.increasing the distance between the source and living tissue                                                                                  3.using shielding ( LEAD -BOXES) to absorb radiation

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iPad Radiation-                                                                   keeping your iPad away from your body, or turning off your wireless signals by using your iPad in airplane mode. This will reduce the RF radiation exposure, but you will still be exposed to ELF radiation.

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iPad Radiation-                                                                   keeping your iPad away from your body, or turning off your wireless signals by using your iPad in airplane mode. This will reduce the RF radiation exposure, but you will still be exposed to ELF radiation.

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Electricity Explained | Simulations, animations and videos to teach electricity

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Radioactivity Explained Home — Electricity Explained | Simulations, animations and videos to teach electricity

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What is a GM Counter / Geiger Muller Counter? - explained simply and clearly

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Who discovered the invisible "radiation"?

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Who discovered the invisible "radiation"?

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Discovery of Radioactivity:

Radioactivity was discovered over 100 years ago by Marie Curie and her husband Pierre, who found that something was being emitted by certain materials; a new kind of energy! Their discoveries created a huge amount of excitement at the time as it was believed that such a powerful new source of energy must be very beneficial. Marie Curie was the first woman to win a Nobel Prize for discovering radioactivity in 1903.

"One of our joys was to go into our workroom at night ... It was really a lovely sight and one always new to us. The glowing tubes looked like faint, fairy lights." - Marie Curie

Benefits of Radioactivity:

Radioactivity has many beneficial uses. Please click on the links below to learn more about how radioactivity benefits society

Risks of Radioactivity:

For a long time, people didn't understand the potential risks associated with radioactivity.

For example, in 1903 Pierre Curie tied a chunk of radium (a highly radioactive material) to his arm for 10 hours. After seeing the severe burns left behind he decided that he had discovered a cure for cancer when all he had done was severely damage his skin.

Issues with radioactivity:

It can damage cells and DNA - High doses can increase the risk of cancer

It can remain radioactive for a long time - While some radiation is short-lived, some radiation can last for thousands of years. This is a problem if the radioactive material is released into the environment.

You need special equipment to detect it - You can't see, hear, smell, taste or feel radioactivity.

However, when handled correctly, radioactivity can be used safely and is quite useful.

For some time after Marie Curie's discovery, a range of dangerous and ridiculous radioactive products were sold to the public - everything from "re-invigorating" Radium water to toothpaste that had Thorium in it; both of which are highly radioactive. The scary thing was that since people didn't know how dangerous they were, companies claimed that using them would make you healthier when in reality they were dangerous and could cause cancer.

Over time people learned that radioactive materials can be very dangerous and there are many examples of people mis-using radioactive material with terrible consequences. When they are handled correctly, however, we can protect ourselves against their harmful radiation and they can be quite useful.

Did you know?

In small doses our bodies are able to repair any cellular damage quickly. This is why medical x-rays are safe as long as the dose is small.

Marie Curie was the first woman to win a Nobel Prize for discovering radioactivity in 1903. Unfortunately she did not know how to safely handle it and died of radiation poisoning.

Radioctive materials occur naturally in nature and are all around us - we are constantly exposed to radiation from rocks in the ground and from cosmic radiation interacting with the atmosphere.

In this remote laboratory experiment you will investigate real samples of different radioactive elements called Americium, Strontium and Cobalt. We will do this to better understand how we can protect ourselves against the harmful radiation from these different radioactive sources.

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Radioactivity was discovered over 100 years ago by Marie Curie and her husband Pierre, who found that something was being emitted by certain materials; a new kind of energy! Their discoveries created a huge amount of excitement at the time as it was believed that such a powerful new source of energy must be very beneficial.

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Created with Hot Potatoes by Half-Baked Software, registered to Andy Darvill.

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GCSE Physics - Alpha, Beta and Gamma Radiation  #33

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Radioactive Shielding Lab

In this lab you will be looking at the amount of radiation you detect from a radioactive source based on the amount of shielding material between the radioactive source and the detector.

When you are ready to start the lab, click on the begin button

Your browser does not support HTML 5.0 Canvas...get a better browser!!!

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Radioactive Shielding Lab In this lab you will be looking at the amount of radiation you detect from a radioactive source based on the amount of shielding material between the radioactive source and the detector. When you are ready to start the lab, click on the begin button Your browser does not support HTML 5.0 Canvas...get a better browser!!!

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Exploring Radioactive Decay

What is radioactivity?

In this FAR Lab experiment you will monitor the radiation from four real radioactive samples; an alpha source, a beta source, a gamma source and an unknown source.

Three very different kinds of radiation come from radioactive materials: - "alpha", "beta" and "gamma". A radioactive sample of each type can be selected, as well as an "unknown" radiation type which you will try to determine.

We are also interested in how the barriers affect the radiation. That is, which barriers can the different types of radiation pass through and which barriers are they unable to pass through. All radioactive emissions are potentially very harmful to humans so it's important to know this.

Clicking the buttons labelled "Source" lines up the detector (called a Geiger counter) with one of 4 real radioactive sources.

Click to enlarge

Clicking the buttons labelled "Absorber" puts a barrier made of a particular material in between the source and the detector.

Click to enlarge

BE SURE TO ALLOW A FEW SECONDS FOR THE TURNTABLES TO MOVE INTO PLACE BEFORE CLICKING ON THE NEXT BUTTON

PART 1: Alpha Radiation

Method:

1. In the column with the Source buttons, click on the "Alpha" source and in the Absorber column, click on "None".

2. Make at least five recordings of the counts and make a note in your lab books

3. Wait for your Count History graph to record at least 30 seconds of data then create a PNG image. OR Download a copy of your data using the Data Browser (please note only the time and counts are saved, not the source or absorber).

4. Repeat this process for the Plastic, Thin Aluminium, Thick Aluminium and the Lead barrier (be sure to leave some time for the graph to stabilise after you change your Absorber).

5. Find the average number of counts for each barrier by averaging your recordings of the counts OR by ruling a horizontal line on your saved plot that runs through the middle of the points.

Question:

What did you notice when you went from no barrier to a barrier?

PART 2: Beta Radiation

Method:

6. Select the Beta source and Absorber None.

7. Repeat steps 2-5 that you did for the Alpha source.

Question:

What do you notice when you go from no barrier to the different kinds of barriers? Was there a difference between the thin and thick piece of Aluminium?
Can radioactive beta material be safely stored?
PART 3: Gamma Radiation

Method:

8. Select the Gamma source and Absorber None.

9. Again, Repeat steps 2-5 that you did for the Alpha source.

Question:

Does anything affect the average number of counts for gamma radiation? If so, how?

PART 4: The "Unknown" Source

Method:

10. Select the Unknown source and Absorber None.

11. Again, Repeat steps 2-5 that you did for the Alpha source.

Question:

What effect do the barriers have on the radiation from the unknown source? What kind of radiation do you think the unknown source is; alpha, beta or gamma?

Discussion:
Go to the discussion questions.

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FARLabs is an award winning virtual laboratory platform connecting Australian high school students to state-of-the-art university equipment for free.

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Penetration power is defined as the ability of radiation to pass through the matter 

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Penetration power is defined as the ability of radiation to pass through the matter 

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Spinning a magnet inside a coil of wire. How an electrical current can be induced in a coil of wire by spinning a magnet perpendicular to the coil.

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Check out us at:http://chemistry.tutorvista.com/nuclear-chemistry/gamma-decay.html Alpha, Beta and Gamma Radiations The radiation is the process in which all the waves or energetic particles travels through a certain medium or space. The radiations are classified into two distinct types. One is ionizing and other is non-ionizing. The radiation word is mainly used to refer the ionizing radiation only.

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Radioactive decay

The radioactive material can collapse its own nucleus structure. At the same time, the nucleus emits some small particles or energy to the outside. The emitted particles and radioactive energy can cause damage to the human body.

In 1895, the German physicist Röntgen detected X-rays, a kind of radiation. Röntgen discovered that when the X-ray is projected directly onto the living body, an image of the bone is formed on the photosensitive plate.

Among the early experimenters, Rutherford and colleagues found three components of radiation from radioactive materials. These components were called α, β, and r-ray. Later, those were identified as 'nuclei of helium atoms,' 'electrons,' and 'high energy photons.'

Half-life period

In radioactivity, Half-life is the interval of time required for one-half of a radioactive sample's atomic nuclei to decay.
If half-life passes again, half of the remaining mass will remain. (1/2, 1/4, 1/8, 1/16, 1/32, ...) The mass is getting smaller and smaller, but it always remains a bit.

\[ N(t) = N_0 {(\frac{1}{2})}^{\frac{t}{t_{1/2}}} \]

\(N(t)\): Mass after time t
\(N_0\): Mass at 't = 0' (initial mass)
\(t_{1/2}\): Half-life period

Radiometric dating

Since radioactive decay proceeds at a constant rate irrespective of external conditions, we can measure the samples' age.

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Half Life Period of a Radioactive Substance - JavaLab

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The radioactive material can collapse its own nucleus structure. At the same time, the nucleus emits some small particles or energy to the outside. The emitted particles and radioactive energy can cause damage to the human body. In 1895, the German physicist Röntgen detected X-rays, a kind of radiation.

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Take close look to the photo and identify how many  sources of radiations 

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Take close look to the photo and identify how many  sources of radiations 

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In this simulation, students will have the opportunity to investigate the decay of two samples of unstable atoms. Students will interact with the simulation in order to decay the unstable samples resulting in a visual and graphical interpretation of half-life.

This simulation was developed through generous funding provided by The Camille & Henry Dreyfus Foundation

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Classroom Resources | Half-Life Investigation | AACT

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In this simulation, students will have the opportunity to investigate the decay of two samples of unstable atoms. Students will interact with the simulation in order to decay the unstable samples resulting in a visual and graphical interpretation of half-life.

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1.Radioactive materials such as used nuclear fuel are transported in special containers called casks                    2. Sources with long half-life values present a risk of contamination for a much longer time                 3.Radioactive waste with a long half-life is buried underground to prevent it from being released into the environment These casks can withstand extreme conditions such as fire, cold and being submerged in water

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1.Radioactive materials such as used nuclear fuel are transported in special containers called casks                    2. Sources with long half-life values present a risk of contamination for a much longer time                 3.Radioactive waste with a long half-life is buried underground to prevent it from being released into the environment These casks can withstand extreme conditions such as fire, cold and being submerged in water

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The virtual Geiger-Müller Tube provides a remarkably realistic simulation of the real equipment without the expense. Identify a random alpha, beta or gamma source, or even use a simulated Ba-137m source for half-life experiments. You can also add cardboard, plastic, and lead barriers to your experiments. The activity guides below are free to reproduce for classroom use.

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The virtual Geiger-Müller Tube provides a remarkably realistic simulation of the real equipment without the expense. Identify a random alpha, beta or gamma source, or even use a simulated Ba-137m source for half-life experiments. You can also add cardboard, plastic, and lead barriers to your experiments.

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Watch alpha particles escape from a polonium nucleus, causing radioactive alpha decay. See how random decay times relate to the half life.

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ITEC 2014 Highlights – Inspiring Australia

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FARLabs is an award winning virtual laboratory platform connecting Australian high school students to state-of-the-art university equipment for free.

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How Do Smoke Detectors Work? | Spec. Sense

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GCSE Physics - Radioactive Decay and Half Life  #35

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Caution

1. This simulation is intended to understand the principle of fission, and the proportions of the model presented may not match the reality.

2. The nucleus was exaggerated and drawed large.

3. The electrons around the nucleus were not shown.

The principle of exponential explosion

When neutrons split a uranium nucleus, it gives off 2×10 ⁸eV of energy. Compared to one TNT molecule producing 30 eV of energy, it is a huge amount (about 6.66 million times difference).
After fission, the mass of the fission byproduct plus the neutron's mass is less than the original mass of uranium.

Mass before division > Mass after division

The mass decreases slightly but produces a lot of energy by Einstein's famous formula E=mc ². The energy from nuclear fission comes as the kinetic energy of the fission byproduct. And part of it is used to generate neutrons, and the remaining part comes out as gamma rays ( r -ray).

Scientists were shocked by this fission. This is because nuclear fission not only produces tremendous energy but also generates neutrons. Usually, when one neutron causes nuclear fission, there are about two to three neutrons emitted. If a newly released neutron causes fission in another nucleus, it can produce 8 to 27 neutrons again, causing a nuclear chain reaction.

Does nuclear fission often occur in nature?

Nuclear fission does not occur in nature. In fact, the chain reaction is only possible with the rare isotope of uranium, ²³⁵U, because only 0.7% of the uranium metal is present. ²³⁸ U, which makes up most uranium metal, absorbs neutrons. Therefore, the chain reaction becomes impossible.

Critical mass

If the fission reaction occurs in a small mass, the chain reaction cannot continue because many neutrons escape through the surface. This is because small objects have a large surface area compared to their volume.
There is a minimum size of a substance that can cause a chain reaction, which is called the 'critical size,' and the mass is called the 'critical mass.'

Atomic bombs were created using rapid fission. Masses smaller than the critical mass do not explode. Multiple chunks of ²³⁵U are suddenly merged to detonate a bomb. Then, the total mass becomes more than the critical mass, so it explodes rapidly.
(Chemistry-The Central Science)

Nuclear power plants are places that allow nuclear fission to occur slowly.

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This simulation is intended to understand the principle of fission, and the proportions of the model presented may not match the reality. The nucleus was exaggerated and drawed large. The electrons around the nucleus were not shown. When neutrons split a uranium nucleus, it gives off 2×10 8eV of energy.

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The processes of natural radioactivity can be divided into three types:

Alpha decay: An atomic nucleus emits a helium-4 nucleus (alpha particle) at about 5 % of the speed of light. The emitting nucleus loses two protons and two neutrons; its mass number (nucleon number) decreases by 4 and its atomic number (proton number) by 2.

Beta decay (more exactly: beta minus decay): An atomic nucleus emits an electron whose speed is very close to the speed of light. As atomic nuclei contain no particles besides protons and neutrons, a transformation of particles is the only explanation for this process. A neutron of the original nucleus turns into a proton, an electron and an anti-electron-neutrino. The mass number (nucleon number) of the emitting nucleus remains constant while the atomic number (proton number) increases by 1.

Gamma decay: An atomic nucleus makes a transition from an excited state to a lower energy level; the composition (number of protons and neutrons) does not change.

For heavy nuclei it often occurs that the daughter nuclei, which have been formed by radioactive decay, decay again to form new daughter nuclei and so on, until finally, after many decay processes, a stable nucleus is left. In this case, we use the term decay series or decay chain. Now, the mass number decreases by 4 or remains constant at any decay. If we divide the mass numbers for the nuclides of the same decay series by 4, the remainder will always be the same (0, 1, 2 or 3). That's why there are four decay series. One of them however (the Neptunium series) contains only synthetic nuclides.

Thorium series (mass numbers of the type 4 n)

Neptunium series (mass numbers of the type 4 n + 1)

(Uranium) Radium series (mass numbers of the type 4 n + 2)

(Uranium) Actinium series (mass numbers of the type 4 n + 3)

This app shows a small part of the table of nuclids in which short notations like Th 232 (consisting of the chemical symbol and the mass number) are used for reasons of space. The number of protons is indicated at the left, the number of neutrons at the beginning of a column. Yellow color is used for alpha decay, blue color for beta decay. After you have chosen one of the decay chains in the selection field on the top right, you can see by repeated mouse clicks on the yellow button ("Next decay") which nuclei are formed one after the other.

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The processes of natural radioactivity can be divided into three types: Alpha decay: An atomic nucleus emits a helium-4 nucleus (alpha particle) at about 5 % of the speed of light. The emitting nucleus loses two protons and two neutrons; its mass number (nucleon number) decreases by 4 and its atomic number (proton number) by 2.

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ITEC 2014 Highlights – Inspiring Australia

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FARLabs is an award winning virtual laboratory platform connecting Australian high school students to state-of-the-art university equipment for free.

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Radioactivity and Half-Life (SwiftStudy Guide)

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A quick guide to half-life calculations with formulas and tips

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Radioaktivní rozpad je proces rozpadu nestabilních atomových jader.