Electromagnetic Spectrum

Question 1

Electromagnetic spectrum

Answer 1

A continuous range of wavelengths, each with different radiation & capacity

Question 2

Radio waves

Answer 2

These have long wavelegnths, 10^3 m, with the capability of transmitting signals long distance

Question 3

Uses of radio waves

Answer 3

Broadcasting and communicating

Question 4

Microwaves

Answer 4

These have wavelengths of 0.3m to 1mm that can penetrate our atmosphere and also cause molecules to vibrate

Question 5

Uses of microwaves

Answer 5

Microwaves can be used for satellite communication, phone networks, cooking and RADAR

Question 6

Dangers of microwaves

Answer 6

Internal tissue heating

Question 7

Infrared

Answer 7

Waves that wavelengths of 700nm to 1000000 nm. They are invisible to humans but felt as heat

Question 8

Uses of infrared

Answer 8

Heating, remote controls, grills, optical fibres, night vision

Question 9

Dangers of infrared

Answer 9

Skin burn

Question 10

Visible light

Answer 10

Comes in a range of colours depending on their wavelength. It is the only part of the spectrum that is visible

Question 11

Uses of visible light

Answer 11

Vision, photography and fibre optics

Question 12

Dangers of light

Answer 12

Blindness

Question 13

Colours of the visible light spectrum

Answer 13

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

Question 14

Ultraviolet

Answer 14

Has a wavelength of 380 - 10 nm. Is blocked by air. Splits into UVA, UVB & UVC

Question 15

Uses of Ultraviolet

Answer 15

Viewing dark areas, fluorescents, rays

Question 16

Dangers of ultra violet

Answer 16

Skin burn

Question 17

X-rays

Answer 17

X-rays have wavelengths of 10nm -0.03nm and can pass through many materials without causing damage

Question 18

Uses of X-rays

Answer 18

Medical scans, identifying atomic structure and providing information on magnetic fields

Question 19

Dangers of X-rays

Answer 19

Long term exposure can damage living organisms

Question 20

Gamma rays

Answer 20

Rays with such high energy that they are produced by radio activity

Question 21

Uses of gamma rays

Answer 21

Sterilisation and medics

Question 22

Dangers of gamma rays

Answer 22

Can kill living cells

Question 23

Doppler effect

Answer 23

This is when frequency and pitch of a wave increases or decreases as a source of sound moves towards or away from an observer, respectively

Question 24

Redshifting

Answer 24

When a light wave moves and gets stretched increasing the wavelength - moving it towards the red end of the spectrum, or even into the invisibility of infrared

Question 25

Wavelength

Answer 25

The distance between identical points in a wave train

Question 26

Displacement

Answer 26

The distance from the equilibrium position

Question 27

Amplitude

Answer 27

Maximum displacement of a particle ( peak or trough max )

Question 28

Period (t)

Answer 28

The time taken for 1 complete wave to pass a point

Question 29

Frequency (f)

Answer 29

number of cycles measured per second

Question 30

Frequency measure

Answer 30

Hertz (hz)

Question 31

Wave speed formula

Answer 31

Wave speed (v) = frequency (f) x wavelength (¥)

Question 32

Diffraction

Answer 32

When waves pass through a gap or around an object of roughly the same size or smaller than their wavelength

Question 33

Diffraction in a large gap

Answer 33

The middle parts of the wave go straight through, with a slight curve at the edges of the wave

Question 34

Diffraction in a small gap

Answer 34

If the gap is smaller than the wavelength of the waves, the waves fan out

Question 35

Sound wave transmission

Answer 35

Sound waves transmit when oscillations or vibrations travel through a material, they pass through a substance causing the particles to vibrate in the direction of the transfer of energy.