3.01-3.03, 3.05, 3.10-3.13 Electromagnetic Spectrum

What is the wave with the lowest frequency and energy?

Radio

What wave has the smallest wavelength?

gamma

Similarities between all EM waves

All transverse, travel at speed of light, travel through a vaccum

What is the speed of light?

3.00 x 10^8 m/s

Name visible light waves in order of lowest to highest frequency?

Red, orange, yellow, green, blue, indigo, violet

Uses of radio waves

Broadcasting and communications

Use of infrared radiation

Heaters and night vision equipment

Uses of microwaves

Cooking and satellite transmissions

Uses of visible light

Optical fibres and photography

Uses of ultraviolet

Detect forged bank notes and security marks, disinfecting water and fluorescent lights.

Uses of X-rays

Medical X-rays. Airport Security.

Uses of gamma rays

sterilising food and medical equipment, detecting and treating cancer.

What is frequency?

number of waves per second

What are the dangers of microwaves?

Internal heating of body tissue

What are the dangers of infrared?

skin burns

Dangers of ultraviolet

damage to surface cells, skin cancer, sun burn, blindness

dangers of gamma rays/x rays

Cancer, mutation

Formula linking wave speed, frequency and wavelength

wavespeed = frequency x wavelength