Topic 2 - Waves and the Electromagnetic Spectrum Flashcards Preview

Physics (Paper 1: 1-3, Paper 2: 4-7) > Topic 2 - Waves and the Electromagnetic Spectrum > Flashcards

Flashcards in Topic 2 - Waves and the Electromagnetic Spectrum Deck (25):
1

Define amplitude

The displacement from the rest position to a crest

2

Define wavelength

The length of a full cycle of the wave from crest to crest

3

Define frequency

The number of complete cycles of the wave passing a certain point per second. It's measured in hertz (Hz).

4

Define period of a wave

The number of seconds it takes to complete one cycle

5

Formula for period of a wave

1 / frequency

6

Define transverse wave

The vibrations are perpendicular to the direction the wave travels

7

Define longitudinal wave

The vibrations are parallel to the direction the wave travels

8

Formulas for wave speed

distance / time
OR
frequency x wavelength

9

State the 3 things that can happen when a wave meets a boundary between two materials

absorbed, transmitted, reflected

10

Explain what happens when a wave is absorbed

The wave transfers energy to the material's energy stores

11

Explain what happens when a wave is transmitted

The wave carries on travelling through new material

12

Explain what happens when a wave is reflected

The incoming ray is neither absorbed or transmitted, but instead is 'sent back'

13

Define refraction

When a wave crosses a boundary between materials it changes speed

14

Define the angle of incidence in refraction

The angle between the incoming (incident) ray and the normal line

15

Define the angle of refraction

The angle between the refracted ray and the normal

16

State whether electromagnetic waves are transverse or longitudinal

Transverse

17

Explain the speed at which electromagnetic waves travel

They all travel at the same speed through a vacuum (space). But they travel at different speeds in different materials, which leads to refraction

18

Order the electromagnetic spectrum from largest to smallest

Radio waves, micro waves, infrared, visible light, ultraviolet, x-rays, gamma rays

19

State a function for radio waves

Broadcasting (TV and radio)

20

State a function for micro waves

Cooking food

21

State some functions for infrared

Infrared cameras (used to detect infrared radiation and moderate temperature), electric heaters, TV remotes

22

State some functions for visible light

Photography and light bulbs

23

State some functions for ultraviolet

Fluorescent lights, security pens

24

State a function for X-rays

To view the internal structure of objects and materials (e.g. bones)

25

State some functions for gamma rays

Killing microbes and detecting cancer