Electromagnetic Waves

What is the electromagnetic spectrum?

The range of all electromagnetic waves arranged by frequency or wavelength

What is the order of the electromagnetic spectrum (low to high frequency)?

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

What happens to wavelength across the EM spectrum?

It decreases as frequency increases

What happens to frequency across the EM spectrum?

It increases from radio to gamma rays

What happens to energy across the EM spectrum?

It increases as frequency increases

Are all electromagnetic waves transverse or longitudinal?

Transverse

Do electromagnetic waves need a medium?

No, they can travel through a vacuum

What is the speed of all electromagnetic waves in a vacuum?

3 × 10^8 m/s

What is visible light?

The part of the EM spectrum that can be detected by the human eye

What are radio waves used for?

Communication such as TV and radio broadcasting

What are microwaves used for?

Cooking and satellite communication

What are infrared waves used for?

Heaters, thermal imaging, and remote controls

What are ultraviolet waves used for?

Sterilisation and causing fluorescence

What are X-rays used for?

Medical imaging of bones

What are gamma rays used for?

Cancer treatment and sterilising equipment

What is a danger of ultraviolet waves?

They can cause skin damage and skin cancer

What is a danger of X-rays?

They are ionising and can damage living cells

What is a danger of gamma rays?

They are highly ionising and can kill cells or cause mutations

What is the key trend in EM waves?

As frequency increases, energy increases and wavelength decreases

What is ionising radiation?

Radiation that has enough energy to remove electrons from atoms, causing damage to cells

Which EM waves are most ionising?

X-rays and gamma rays