In this explainer, we will learn how to identify applications of nuclear radiation.
Atoms contain nuclei. Some nuclei are unstable, which means they can change spontaneously. We call this nuclear decay. When a nucleus undergoes a nuclear decay, it releases nuclear radiation in the form of particles and electromagnetic waves.
The energy category for unstable nuclei is called nuclear energy. When a nucleus emits nuclear radiation, some of its nuclear energy can be transferred to other categories of energy. This energy can be used in lots of different ways.
One of the most important ways we use this energy is generating electricity. Nuclear power stations are used to transfer energy from nuclear fuel to electrical energy. Nuclear fuel is a radioactive material that emits large amounts of nuclear radiation and so transfers lots of energy in a small time.
In nuclear power stations, the energy released by the nuclear fuel is transferred to the thermal energy of water, which causes the water to boil.
When the water boils, it becomes steam. Steam can be used to rotate turbines and power an electrical generator. In this process, the thermal energy is transferred to electrical energy.
Example 1: Radiation and Electricity Generation
Which of the following statements correctly describes how energy from nuclear radiation is used in electricity generation?
- Energy from nuclear radiation is used to produce electromagnetic waves.
- Energy from nuclear radiation is used to boil water.
The answer is B. Energy from nuclear radiation is used to boil water.
When a radioactive element decays, it releases nuclear radiation. This nuclear radiation can take the form of particles or electromagnetic waves.
When a nucleus emits nuclear radiation, some of its nuclear energy can be transferred to the thermal energy of water. This causes the water to boil.
When the water boils, it produces steam that causes a turbine to rotate. This powers an electricity generator.
Example 2: Nuclear Radiation and Electricity Generation
Which of the following statements correctly describes how the emission of nuclear radiation by decaying atomic nuclei can be used in electricity generation?
- The energy of the particles and waves emitted as nuclear radiation can be transferred to thermal energy.
- Batteries that transfer the chemical energy of the emitted nuclear radiation to electrical energy can be made.
The answer is A. The energy of the particles and waves emitted as nuclear radiation can be transferred to thermal energy.
When a radioactive element decays, it releases nuclear radiation. This nuclear radiation allows energy to be transferred from nuclear energy to the thermal energy of water. This causes the water to boil.
When the water boils, it produces steam. Steam can be used to rotate turbines. This powers an electricity generator that transfers energy to electrical energy.
Batteries can be used to transfer chemical energy to electrical energy. However, this kind of battery does not use radiation to produce electricity.
Nuclear power stations do not use batteries to generate electricity.
The process of generating electricity in nuclear power plants also produces nuclear waste. When an atom undergoes a nuclear decay and emits nuclear radiation, the nucleus of the atom changes. When nuclear fuel emits nuclear radiation, it decays into nuclear waste.
Nuclear waste emits much less nuclear radiation than nuclear fuel does, so it cannot transfer very much energy. Hence, nuclear waste is not useful for producing electricity and is disposed of.
Example 3: Problems with Using Nuclear Energy for Electricity Generation
Which of the following statements correctly describes a problem associated with using nuclear energy for electricity generation?
- A nuclear reactor can explode like a nuclear bomb.
- Radioactive waste is produced.
The answer is B. Radioactive waste is produced.
When nuclear fuel decays, it releases nuclear radiation. Nuclear radiation transfers some of the nuclear energy of the nucleus to the thermal energy of water. This causes the water to boil and produce steam that is used to generate electricity.
When a substance decays, the nuclei of its atoms change. When nuclear fuel decays, it changes into nuclear waste. Nuclear waste is radioactive but does not transfer as much energy as nuclear fuel does, so it is not useful for generating electricity. Hence, nuclear waste must be disposed of.
The reactors in nuclear power stations are very closely monitored. The amount of nuclear radiation produced is strictly controlled to ensure that nuclear reactors are safe and will not explode.
As well as generating electricity, there are many other applications of radioactivity.
Radioactivity has many medical uses. For example, nuclear radiation is often used in medical imaging. Images can be created of the inside of the body in order to diagnose illnesses and ailments. Radioactive substances can be used as “tracers” to help make these images clearer. Different tracers are absorbed by different parts of the body. By monitoring the radiation emitted by a tracer, an image can be formed of a particular body part.
Radioactivity also has other uses in medicine. Nuclear radiation can damage cells. This means nuclear radiation is very useful for treating cancer. Nuclear radiation can be directed toward the body so that it kills cancer cells without damaging too many healthy cells. This kind of treatment is called radiotherapy.
Nuclear radiation is also useful in agriculture.
Pests, such as insects, often eat crops. This damages the crops and reduces the amount that farmers can sell. Insects often lay eggs on crops. When the eggs hatch, this produces more insects that cause more damage.
However, nuclear radiation can be used as a form of pest control. Nuclear radiation can kill eggs laid by insects. This allows farmers to control the number of insects and reduce damage to their crops.
Farmers can also use radiation to change the characteristics of their crops. Nuclear radiation can cause changes to the DNA of plant cells. These are called mutations. Mutations can give crops useful properties. For example, they can make them easier to grow or more nutritious.
Example 4: Nuclear Radiation in Agriculture
Which of the following is a current agricultural use of nuclear radiation?
- Producing useful mutations in plants
- Transferring energy to plants and animals to make them grow faster
The answer is A: Producing useful mutations in plants.
Nuclear radiation can cause changes in a plant’s DNA called mutations. These mutations can change the characteristics of the plant in useful ways. For example, it can make plants easier to grow.
Nuclear radiation does transfer energy to plants, but it does not make them grow faster. The energy that is transferred causes the mutations in the plants’ DNA.
Nuclear radiation also has industrial uses. This means nuclear radiation can be useful for building and developing products.
For example, nuclear radiation can be used to find very small faults in products. Radiation can be used to produce detailed images of the products that reveal flaws that are too small to be easily seen by the eye.
Some industries need very high temperatures to make their products. Nuclear radiation can be used to generate these high temperatures, as radiation transfers nuclear energy to thermal energy.
Nuclear radiation is also useful for mining.
Often, crude oil and natural gas are mined, as they are useful for generating electricity. However, oil and gas can be difficult to find, as they form underground.
Nuclear radiation techniques can be used to locate oil and gas underground. The underground rocks that contain oil and gas also contain radioactive elements. This means that rocks that emit radiation are likely to contain oil and gas. Radiation detectors can be used to find these rocks and hence locate the oil and gas.
Nuclear radiation is also used in space exploration.
Radioactivity can be used to generate the electricity needed in a spacecraft. Nuclear radiation transfers energy from the nucleus to thermal energy that is used to generate electricity.
This is very similar to the process that takes place in nuclear power plants, which we discussed at the beginning of this explainer. However, there is a key difference between these two processes.
In nuclear power plants, the energy of nuclei causes water to boil and produce steam. However, in a spacecraft, we do not generate electricity by boiling water. Instead, we use a nuclear battery. This means electricity can be generated without boiling water.
Example 5: Nuclear Radiation in Space Exploration
Which of the following is a current use of nuclear radiation in space exploration?
- Propelling rockets
- Protecting astronauts from cosmic rays
- Transferring energy of nuclear radiation to thermal energy
The answer is C: Transferring energy of nuclear radiation to thermal energy.
Nuclear radiation transfers the energy of nuclei to thermal energy. In a spacecraft, a nuclear battery uses this thermal energy to generate electricity.
Rockets are propelled by the fuel in their engines. This fuel is not radioactive, so it does not produce radiation.
Spacecrafts are designed to protect astronauts from cosmic rays. Spacecrafts are built from materials that do not allow cosmic rays to pass through them. This prevents the astronauts from coming into contact with cosmic rays.
Now that we have discussed some useful applications of radioactivity, let us summarize what has been learned in this explainer.
- In nuclear power plants, nuclear radiation transfers nuclear energy to the thermal energy of water. This causes the water to boil, which produces steam that can drive an electrical generator.
- In nuclear power plants, nuclear fuel decays into nuclear waste that needs to be disposed of.
- Radioactivity is used in medicine to diagnose and treat illnesses.
- In agriculture, nuclear radiation is used to kill insects and produce useful mutations in plant crops.
- Nuclear radiation has industrial uses; for example, detecting flaws in products and producing high temperatures.
- We can use nuclear radiation to locate oil and gas underground.
- Nuclear radiation is used to generate electricity in spacecrafts.
- In spacecrafts, nuclear radiation transfers nuclear energy to thermal energy. Then, nuclear batteries use this thermal energy to generate electricity.