2. REVISION

4. What wave is missing and how does its frequency compare with gamma waves?(2)

5. Which three types of waves are used in communications (3)

6. Which electromagnetic waves can be used to cook these? (2)

7. Which electromagnetic are used by each of these devices? (2) REMOTE CONTROLE MOBILE PHONE

8. What is the difference between digital signals and analogue signals? (2)

9. Explain how radio waves are received by houses on the other side of hills (3)

10. Between which two letters is the wavelength? (1)

11. Which three types of waves cause cancer? (3)

12. Give two advantages of digital signals over analogue signals? (2)

13. Explain how microwaves cook food through to the centre (3)

14. Between which two letters is the amplitude? (1)

15. Why are dark skinned people less at risk than light skinned people ? (2)

16. How do infrared waves cook through to the centre of food?(2)

17. Explain how microwave TV signals are sent long distances (3)

18. Why do S waves show us there is a liquid layer inside the Earth?(3)