P3.3- Electromagnetic waves

Question 1

What are the 7 electromagnetic waves found in the electromagnetic spectrum in order of increasing wavelength

Answer 1

Gamma, X-ray, UV, Visible, Infrared, Microwaves, Radio

Question 2

What is the highest frequency electromagnetic wave

Answer 2

Gamma waves

Question 3

What is the highest energy electromagnetic wave

Answer 3

Gamma waves

Question 4

What is the speed of EM waves in a vacuum

Answer 4

3x10⁸ m/s

Question 5

A wave transmits energy from…

Answer 5

source to absorber
(light source to eye)

Question 6

What properties are shared by all EM waves [3]

Answer 6

1. They are all transverse waves
2. They travel at the same speed
3. They can travel through a vacuum

Question 7

State + explain uses of radio waves [2]

Answer 7

1. Communications
2. radio waves have long wavelengths and can travel long distances without losing quality

Question 8

State+ explain uses of microwaves [2]

Answer 8

1. Cooking
2. microwaves are absorbed and heat fat/water

Question 9

State uses of infrared radiation [3]

Answer 9

1. Cooking food- transfers thermal energy
2. infrared cameras
3. short range communications

Question 10

State + explain uses of visible radiation [2]

Answer 10

1. Illuminating + fibre optics
2. they reflect best in glass
   - other waves have wavelengths that are too long/short

Question 11

State + uses of UV radiation [3]

Answer 11

1. Sterilization - it kills bacteria
2. Energy efficient lamps - it radiates low heat but high energy
3. sun tanning

Question 12

State and explain uses of X-rays [2]

Answer 12

1. Medical imaging and treatment
2. They are very high energy- can easily penetrate body tissues

Question 13

State and explain uses of Gamma rays [2]

Answer 13

1. Medical treatments
2. Radiotherapy in the treatment of cancer

Question 14

How does UV radiation affect body tissues [2]

Answer 14

1. UV radiation can cause cancer when skin is exposed to it
2. It can cause blindness if eyes are overexposed to UV radiation

Question 15

How do X-rays affect body tissues [2]

Answer 15

1. X-rays are ionising so they can damage or kill cells
2. Can cause mutations that could lead to cancer

Question 16

How do gamma rays affect body tissues [2]

Answer 16

1. Even more ionising that X-rays
2. So they can cause cell mutations- and cell death