Electromagnetic waves

Question 1

Are electromagnetic waves longitudinal or transverse waves

Answer 1

Transverse waves

Question 2

Describe the order of the electromagnetic spectrum from lowest to highest energy

Answer 2

Radio waves →Micro waves →Infra red →Visible light → Ultra violet → X-rays → Gamma rays

Question 3

Describe the properties of radio waves

Answer 3

They are used mainly for communication

1) Radio and TV signals can be sent by radio waves
2) Very short wavelength
3) They have to be in direct sight to the receiver so they cant be far away
4) They can be used to send radio signals around the world

Question 4

Describe the properties of microwaves

Answer 4

Used for satellites and cooking

1) Satellite tv and phones
2) Transfer energy from source to the absorber

Question 5

Describe the properties of infrared radiation

Answer 5

Its given out by all objects.
the hotter the object the more infrared it gives out.
It can also be used to warm things - electric heater release infrared

Question 6

Describe the properties of visible light

Answer 6

Fibre optic cables use visible light to send data.
Optical fibre are thin glass or plastic tubes that carry data.
They often send information to telephone or computers.
The in information is sent as light rays hat bounce back and forth along the fibre

Question 7

Describe the properties of ultraviolet radiation

Answer 7

It is produced by the sun.

Energy efficient lights use UV radiation to produce visible light

Question 8

Describe the properties of X rays and gamma rays

Answer 8

They are used in medicine.
X rays pass easily through flesh but not though bones or metal.
They can treat people with cancer - this is because they can kill cells.

Gamma rays can also kill cells.
They can be used to treat cancer.