1. Find equivalents:

2. Complete the sentences:

1. Investigating nuclear physics scientists discovered

2. We are provided with heat and light for our homes due to

3. Temperature means how much energy

4. The higher the temperature,

5. Specific temperatures at which changes of state occur are known as

6. Density is

7. Radiation is

8. There are three types of radiation, known as

9. The weakest type of radiation is

10. The word isotope means «same place» because

11. Each isotope has a various amount of

12. Hydrogen gas can exist naturally in three isotopic forms:

13. To produce energy nuclear power stations use such nuclear reaction as

14. Fission causes

15. A nuclear reaction that takes place naturally is called

16. Nuclear fusion occurs when

17. Scientists are trying to develop nuclear fusion as an alternative to nuclear fission because

3. Answer the questions:

1. What does nuclear physics study?

2. What does temperature determine?

3. Why does the change of state occur?

4. What temperature is called absolute zero?

5. Why does the metal object have the greater density than a wooden one?

6. What is called a chain reaction?

7. What are radioactive substances composed of?

8. What type of radiation has positive electrical charges?

9. Why gamma rays are considered to be a pure form of radiation?

10. What atomic particles are beta rays made up of?

11. Do isotopes have identical chemical and physical properties?

12. Why are isotopic physical properties various?

13. What gas can exist naturally in common, heavy and radioactive forms?

14. What nuclear reaction occurs only artificially?

15. What nuclear reaction occurs only naturally?

16. How does fission happen?

17. What does nuclear fission result in?

18. Where is nuclear fusion created?

19. What temperature is necessary for nuclear fusion to occur?