science:Physics

science:Physics

1. transfer energy as radiation from the source of the waves to an absorber

2. can travel through a vacuum such as in space

3. travel at the same speed through a vacuum or the air

4. Electromagnetic waves can travel at 300,000,000 m/s through a vacuum.

5. red light has the lowest frequencies of visible light

6. violet light has the highest frequencies of visible light

7. Radio waves can be produced by oscillations in electrical circuits. When radio waves are absorbed by a conductor, they create an alternating current. This electrical current has the same frequency as the radio waves

8. High frequency microwaves have frequencies which are easily absorbed by molecules in food. The internal energy of the molecules increases when they absorb microwaves, which causes heating

9. Infrared (IR) light is used by electrical heaters, cookers for cooking food, short-range communications like remote controls, optical fibres, security systems and thermal imaging

10. infrared light has frequencies which are absorbed by some chemical bonds. The internal energy of the bonds increases when they absorb infrared light, which causes heating.

11. Visible light is the light we can see, so is used in photography and illumination. It is also used in fibre optic communications, where coded pulses of light travel through glass fibres from a source to a receiver

12. We cannot see ultraviolet (UV) light but it can have hazardous effects on the human body. Ultraviolet light in sunlight can cause the skin to tan or burn.

13. Gamma rays are ionising which means it is harmful to our bodies