Electromagnetic Waves

1. Radiowaves

1.1. longest wavelength and smallest energy electromagnetic wave

1.2. so small it is impossble to detect them without proper instrument

1.3. use in the exploration of space to record distance of objects

1.4. produced by oscillating antenna

2. microwaves

2.1. Microwaves is a misnomer

2.2. Wavelength range of this radiation is about 3.0cm to 1.0 cm

3. Infra-red waves

3.1. JUst below the visible spectrum is infrared radiation

3.2. they are longer wavelength light rays

3.3. many molecules tend to resonate or vibrate easily when exposed to infrared radiation

4. Visible light

4.1. Occupying a very small part of the entire electromagnetic spectrum

4.2. the only range of energies that human eyes can detect

4.3. the visible spectrum conveys the world to our brains in brilliant hues and shades

5. X-ray

5.1. a newer type of radiation

5.2. has the ability to pass through many materials that absorb visible light

5.3. highly energetic form of light not visible to human eyes

5.4. objects at very high temperature emit most of their energy as X-rays

6. Electromagnetic waves are not mechanical waves

7. All electromagnetic waves are transverse waves that travel with the same speed in vacuo and state the magnitude of this speed.

8. Group

8.1. radio waves

8.2. infra-red

8.3. visible light

8.4. ulta violet

8.5. X-rays

8.6. gamma rays

9. travel at the speed of 3 x 10^8 m/s in vacuum

10. Ultra violet

10.1. Discovered in 1801 because of its effects on photogenic plates

10.2. the sun is a strong emitter of UV radiation

10.3. the earth is shielded by the ozone layer

11. Gamma rays

11.1. Highest energy electromagnetic waves

11.2. very short wavelength

11.3. caused by radioactive decay also produced by nuclear fusion

11.4. unstable nuclei emit gamma rays

11.5. more energetic than x rays and can pass through concrete and metal

11.6. very dangerous can kill living cells

11.7. seen from nuclear bomb

11.8. used in cancer treatment