Electromagnetic Waves

What type of spectrum do electromagnetic waves form?

A continuous spectrum.

Order the types of electromagnetic radiation from lowest to highest frequency.

● Radio waves

● Microwaves

● Infrared

● Visible Light

● Ultraviolet

● X-rays

● Gamma Rays

How do the speeds of EM radiation differ in a vacuum and in air?

Electromagnetic waves all travel at the same speed in a vacuum and in air.

In which direction (relative to the normal) do waves refract when entering a denser medium?

• They bend towards the normal

• The angle of refraction is less than the angle of incidence

Where do gamma rays originate from?

they originate from changes in the nuclei of atoms.

What health effects can ultraviolet waves cause?

• They can cause the skin to age prematurely

• The can increase the risk of developing skin cancer

What health effects can X-rays and Gamma rays cause?

• They are ionising radiation so can cause mutations in genes

• They can lead to increased risk of developing various cancers

Give three practical uses for infrared radiation.

1. Electrical heaters

2. Cooking food

3. Infrared cameras

Give two practical uses for microwave radiation

1. Satellite communications

2. Cooking food

Give two practical uses for radio waves.

1. Television transmission

2. Radio transmission