P5.2

Question 1

What waves are on the magnetic spectrum (in order of increasing frequency).

Answer 1

Radio waves, 
microwaves, 
infrared, 
visible light, 
ultraviolet, 
X-rays
Gamma rays

Question 2

What are electromagnetic waves?

Answer 2

Electromagnetic waves consist of oscillating electric and magnetic fields. The fields are oscillating in a direction at 90° to the direction of the wave.
All electromagnetic waves travel through a vacuum at 3 X 10^8 m/s (the speed of light)

Question 3

What do electromagnetic waves do?

Answer 3

They transfer energy from sources to absorbers. Some waves transfer info.

Question 4

How do you calculate frequency of a wave

Answer 4

Frequency = wave speed / wave length

Question 5

How are electromagnetic waves used for communication?

Answer 5

Your phone communicated with trans,otters using microwaves. Microwaves are also used to communicate with satelites and for WiFi and bluetooth systems.

Remote controls use infrared to communicate with televisions.

Question 6

How are microwaves used to heat up food?

Answer 6

In. Microwave oven, the water and fat in food absorb the microwaves which heats up the outside of food. Conduction transfers energy to the middle.

Question 7

How are gamma rays useful in medicine?

Answer 7

Gamma rays can kill cancer cells and also bacteria on food

Question 8

How are ultraviolet rays useful in medicine

Answer 8

It kills bacteria in water

Question 9

How are X rays useful in medicine

Answer 9

X-rays can kill skin cancer or other cancer cells

Question 10

Which waves are dangerous and why?

Answer 10

Ultraviolet radiation can damage the DNA in the cells of your skin.
These cells can grow rapidly and cause skin cancer
X-RAYS can also da,age your cells and cause cancer
GAMMA RAYS can also damage or kill the cells in your body.