Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics - S2 > Waves and Sound Waves > Flashcards

Waves and Sound Waves Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What do all waves transfer?

A

Energy from one point to another through vibrations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do some waves transfer and examples?

A

Information - Sound, Light, Radiowaves, Microwaves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a mechanical wave? Examples?

A

A wave that travels energy through one point to another using matter

(Water waves, Sound waves, Secondary Earthquake waves)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a transverse wave? Examples?

A

A wave in which the vibrations are perpendicular to the direction of travel.

(Water waves, Secondary Earthquake waves, EM Spectrum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the two types of mechanical waves?

A

Transverse and longitudinal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do no waves transfer?

A

Matter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the equation for frequency?

A

F = 1/T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the unit for frequency?

A

Hertz - Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the time period?

A

The time one full wavelength of an wave to pass by a certain point.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is frequency?

A

The number of wavelengths that pass through a point in one second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is wavelength?

A

The distance between two identical points on neighbouring waves.

Symbol - lamda - look in book

E.g Two peaks, Crests, Rarefactions or Compressions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is a longitudinal wave? Examples?

A

A wave in which the vibrations are parallel to the direction of wave travel

Sound waves, Ultrasound waves, Primary earthquake waves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are compressions and rarefactions?

A

Sections that are pushed together are called compressions

Sections that are stretched out are called rarefactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is hearing range of a healthy young person?

A

The range of frequencies you can hear is called your hearing
range.

The hearing range of a healthy young person is 20 Hz to 20 000 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What size of an amplitude on a graph means a loud quiet sound?

A

A large amplitude = loud
A small amplitude = quiet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What amount of waves on a graph means high or low frequency?

A

A high number of waves = high frequency
A low number of waves = low frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is ultrasound?

A

Any frequency above 20,000 Hz cannot be heard by
humans. This sound is referred to as ultrasound.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How can echoes be used?

A
  1. Measuring the depth of water
  2. Measuring the depth of fish under a boat
  3. Measuring the speed of a car with a speed gun
15
Q

How is ultrasound used?

A

Ultrasound can be used to measure the foetal head diameter.

Ultrasound can be used in industry to detect defects in metals.

16
Q

What is the equation to find the depth of a basin of water etc

A

s = d/t
Never use depth for d always use distance

16
Q

What is the speed of sound in air?

A

330 - 340 m/s

17
Q

What is the speed of light in air?

A

This speed is referred to as the speed of light c.
C = 300,000,000 m/s or 3 x 10 to the power of 8 m/s.

18
Q

What is the equation to find the speed of a wave?

A

V = f X Lamda

19
Q

Label the different parts of a wavelength?

A

Look in Book :D

20
Q

What is the difference between mechanical and EM waves?

A

Mechanical waves – produced by a disturbance in a material medium

EM waves – produced by a disturbance in the form of a varying electric and magnetic field.

Mechanical waves require matter while Em waves do not

21
Q

What is radar and how is it used?

A

Radar is often E.M waves fired above water to detect aerial objects.

Often used by the military to detect planes/missiles etc in the sky as the E.M waves travel at 300,000,000 m/s

22
Q

What is sonar and how is it used?

A

Sonar is often sound waves fired under water to detect underwater objects.

Often used by the military to detect submarines etc under boats as sound waves travel much faster than submarines

23
Q

At what speed do EM waves travel?

A

All electromagnetic waves travel at the same speed.

In a vacuum (space), they travel at 300,000,000 m/s!

24
Q

How far does an E.M wave travel in a second?

A

This is approx. 7.5 times around the equator per second.

25
Q

How long does light take from the sun take to reach us?

A

It takes the light from the sun 8 minutes to reach us here on Earth.

26
Q

What are EM waves made up of?

A

Electromagnetic waves are transverse waves made up of electric and magnetic fields.

27
Q

How does the energy of EM waves change and what do they depend on?

A

⚫ The amount of energy carried by an electromagnetic wave depends on the wavelength: the shorter the wavelength, the higher its energy.

⚫ Wavelength and frequency are linked properties of a wave: the shorter the wavelength, the higher its frequency.

⚫ So, frequency also tells you about the energy of a wave:
the higher its frequency, the higher the energy.

28
Q

What is the order of EM waves in order of changing energy and wavelength?
Biggest wavelength to smallest

A

Electromagnetic waves form a continuous series in order of changing
wavelength, frequency and energy. This series is called the electromagnetic spectrum.

Radio waves microwaves infrared visible light UV X-rays Gamma rays
0.1m + 10cm 1mm 0.01mm 100nm 1nm 0.01nm

28
Q

What happens when light hits a surface?

A

When electromagnetic waves hit a surface, they can be reflected, absorbed or transmitted.

How the waves behave, depends on their energy and the type of material. For example, light waves are reflected by skin but X-rays pass straight through.

29
Q

What does an EM wave do to the temperature of an object?

A

If electromagnetic waves are absorbed, some of their energy is absorbed by the material. This usually increases the temperature of the material.

30
Q

What surfaces our good at reflecting light? Examples?

A

Some surfaces can reflect electromagnetic waves. Shiny surfaces are good reflectors of light waves.

A mirror reflects most of the light waves that hit it. When waves are reflected, some of their energy may also be absorbed by the material.

The curved satellite dish reflects microwaves from a satellite to the receiver. Light reflects into our eyes so we could see

30
Q

What are uses of each EM wave?

A

Radio waves: Bluetooth and radios in cars.
Microwaves: Heating food and mobile phones.
IR: Sensors on cars for reversing.
Visible light: Seeing things.
UV: Detecting forced bank notes.
X-Ray: Detecting broken bones.
Gamma: Used in medical imaging such as PET scans.

31
Q

How can EM waves be harmful?

A

Microwaves cause internal heating of body tissues.

Infrared radiation is felt as heat and causes skin burns.

Certain wavelengths of ultraviolet can damage skin cells and lead to skin cancer.

Intense visible light can damage eyes.

X-rays can gamma rays damage cells, which may lead
to cancer.

32
Q

What happens to the properties of a wavelength as it travels into deep water?

A

Speed - Increases
Wavelength - Increases
Frequency - Constant

33
Q

What happens to the properties of a wavelength as it travels into shallow water?

A

Speed - decreases
Wavelength - decreases
Frequency- constant

34
Q

What happens to the reflected ray when travelling from deep water into shallow water?

A

It bends towards the normal
i > r

35
Q

What happens to the reflected ray when it travels from shallow to deep water?

A

It bends away from the normal
r > i

36
Q

When a ray is reflected what is the relationship between the angle of incident and angle of reflection?

A

They are equal
i = r

Physics - S2 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions