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4th Form Physics > Waves (Basic) > Flashcards

Flashcards in Waves (Basic) Deck (59)
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1
Q

What is a wave?

A

A wave is an oscillation in a medium.

Waves can transfer energy and information.

2
Q

What is an ‘oscillation’?

A

An oscillation is another word for a vibration.

3
Q

When discussing waves, what is meant by the word ‘medium’?

A

A ‘medium’ is the material through which a wave passes.

4
Q

What is the medium for surface waves in the ocean?

A

Water is the medium.

5
Q

What is the medium for sound waves in this room?

A

Air is the medium.

6
Q

What is the medium for waves on a slinky?

A

The slinky is the medium.

7
Q

Give the definition of ‘wave direction’

A

‘Wave direction’ is the direction in which the wave transfers energy.

8
Q

Give the definition of ‘a transverse wave’

A

A transverse wave is a wave where the medium oscillates perpendicular to the direction of energy transfer.

9
Q

Give the definition of ‘a longitudinal wave’

A

A longitudinal wave is a wave where the medium oscillates parallel to the direction of energy transfer.

10
Q

Give three examples of transverse waves

A

Waves on the surface of the ocean
Light waves
Infra-red waves
(also: all electromagnetic waves are transferse, e.g. radio, microwave, UV)

11
Q

Give three examples of longitudinal waves

A

P-waves from an earthquake
Sound waves
Ultrasound waves

12
Q

What is meant by the ‘wavelength’ of a wave?

A

The wavelength is the distance between two neighbouring peaks (or two troughs) on a wave.

13
Q

What are the units of wavelength?

A

Wavelength is a length, and like all lengths it is measured in metres. (m)

14
Q

What is meant by the ‘period’ or ‘time period’ of a wave?

A

The time period of a wave is the time for one complete oscillation to occur.

15
Q

What are the units of ‘period’?

A

The ‘period’ or ‘time period’ of a wave is a time, and like all times it is measured in seconds. (s)

16
Q

What is meant by the frequency of a wave?

A

The number of complete oscillations that pass a point, per second.

17
Q

What are the units of frequency?

A

The units of frequency are Hertz. (Hz)

18
Q

Define the ‘amplitude’ of a wave.

A

The amplitude is the maximum displacement caused by a wave.

OR The amplitude is the displacement from the line of zero displacement to the peak of a wave.

19
Q

What are the units of amplitude?

A

Amplitude is a distance, so the units of amplitude are metres. (m)

20
Q

You hear two sound waves. The second wave has the same frequency as the first, but a bigger amplitude. How does it sound different?

A

It sounds louder.

You have to say ‘louder’ at GCSE. ‘Loud’ would be marked wrong.

21
Q

You hear two sound waves. The second wave has the same amplitude as the first, but a bigger frequency. How does it sound different?

A

It sounds higher pitched.

You have to say ‘higher’ at GCSE. ‘High’ would be marked wrong.

22
Q

You see two light waves. The second wave has the same amplitude as the first, but a bigger frequency. How does it look different?

A

It is a different colour.

It would be closer to the blue end of the spectrum that the first light wave

23
Q

You see two light waves. The second wave has the same frequency as the first, but a bigger amplitude. How does it look different?

A

It looks brighter.

You have to say ‘brighter’ at GCSE. ‘Bright’ would be marked wrong.

24
Q

What does the symbol ‘λ’ stand for, and what units is it measured in?

A

The symbol ‘λ’ stands for wavelength. Wavelengths are measured in metres. (m)

25
Q

What does the symbol ‘f’ stand for, and what units is it measured in?

A

The symbol ‘f’ stands for frequency. Frequencies are measured in Hertz. (Hz)

26
Q

In the waves topic, what does the symbol ‘T’ stand for, and what units is it measured in?

A

In the waves topic, ‘T’ stands for the ‘time period’ of a wave. It is measured in seconds. (s)

27
Q

In the waves topic, what does the symbol ‘A’ stand for, and what units is it measured in?

A

In the waves topic, ‘A’ stands for the amplitude of a wave. Amplitudes are measured in metres. (m)

28
Q

What equation links the number of waves that pass a point, the wave frequency and the time taken?

A

frequency = number of waves ÷ time taken (for them to pass a point)

29
Q

120 waves pass a point in 10 seconds. What is the wave frequency?

A

120 ÷ 10 = 12 Hz

This means 12 waves every second

30
Q

5 waves pass a point in 10 seconds. What is the wave frequency?

A

5 ÷ 10 = 0.5 Hz

This means half a wave every second

31
Q

Name two things that all electromagnetic waves have in common

A

They all travel at the speed of light in a vacuum

They are all transverse waves

32
Q

Which electromagnetic wave is used to transmit TV signals?

A

Radio waves

33
Q

Which electromagnetic wave is also known as ‘thermal radiation,’ and is emitted by warm objects?

A

Infrared radiation

34
Q

Which electromagnetic wave can be used to view security markings?

A

Ultraviolet

35
Q

Which electromagnetic wave is used to create shadow pictures of bones?

A

X-rays

36
Q

Which electromagnetic wave is used to sterilise medical equipment?

A

X-rays OR gamma rays

37
Q

Which electromagnetic wave is used to cook a cheese toastie on a grill?

A

Infrared radiation

38
Q

Which waves are used for both radar and for mobile phone transmissions?

A

Microwaves

39
Q

Which electromagnetic wave can cause eye damage?

A

Ultraviolet radiation

40
Q

Which electromagnetic wave can cause burns to the skin?

A

Infrared radiation

41
Q

Which electromagnetic wave can be detected by the human eye?

A

Visible light

42
Q

Which electromagnetic wave can cause skin cancer?

A

Ultraviolet radiation

43
Q

Which electromagnetic wave can be used to kill cancer cells?

A

X-rays OR gamma rays

44
Q

What is the risk of exposure to X-rays and gamma rays?

A

They can both cause cancer

45
Q

Which waves have the higher frequency, radio or microwaves?

A

Microwaves

46
Q

Which waves have the longer wavelength, ultraviolet or infrared?

A

Infrared

47
Q

Which waves have the lower frequency, X-rays or microwaves?

A

Microwaves

48
Q

Which waves have the shorter wavelength, gamma rays or visible light?

A

Gamma rays

49
Q

Which waves travel faster in a vacuum, visible light or ultraviolet?

A

Trick question! They travel at the same speed. All electromagnetic waves travel at the speed of light in a vacuum.

50
Q

Which waves have the shorter wavelength, visible light or microwaves?

A

Visible light

51
Q

Which waves have the higher frequency, X-rays or ultraviolet?

A

X-rays

52
Q

Which waves have the longer wavelength, microwaves or infrared?

A

Microwaves

53
Q

Which waves have the lower frequency, visible light or radio waves?

A

Radio waves

54
Q

Which of these are longitudinal waves: radio waves, visible light or ultraviolet radiation?

A

Trick question! None of them. All electromagnetic waves are transverse.

55
Q

What is the highest frequency sound a human being can hear?

A

20,000 Hz

56
Q

What is the name for sound waves with a frequency above 20,000 Hz?

A

Ultrasound

57
Q

What is the lowest frequency sound a human being can hear?

A

20 Hz

58
Q

Are ultrasonic waves transverse or longitudinal?

A

Ultrasonic waves are longitudinal. (All sound waves are longitudinal. Ultrasound is simply sound that is too high pitched for us to hear)

59
Q

Name two uses of ultrasonic waves

A
Any two from:
• Cleaning jewellery
• Checking for cracks in railway tracks
• Echolocation (Sonar)
• Imaging the foetus in the womb
(You must use this phrase! "pictures of babies" = zero marks)