Sound Waves

Question 1

What is the unit for frequency?

Answer 1

Hertz (Hz)

Question 2

Longitudinal Wave

Answer 2

The vibrations are parallel to the direction of energy transfer.

Question 3

Transverse Wave

Answer 3

The vibrations are perpendicular (90 degreees) to the direction of energy transfer.

Question 4

Amplitude

Answer 4

The maximum distance of a wave from the equilibrium position.

Question 5

Time Period

Answer 5

Time for one wave to pass

Question 6

Frequency

Answer 6

Number of waves that pass a point in a unit of time

Question 7

Wavelength

Answer 7

Distance between two peaks of a wave

Question 8

How do waves transfer energy without transferring matter?

Answer 8

A wave causes the particles to oscillate, transferring energy from one point to another without the need for any matter to be physically moved.

Question 9

Wave speed, frequency and wavelength equation

Answer 9

Wave speed = frequency x wavelength

c=fλ.

Question 10

Time Period and frequency equation

Answer 10

Frequency = 1/time period

F = 1/T

Question 11

Name the electron magnetic spectrum from low to high frequency

Answer 11

Radio
Microwave,
Infrared
Visible
Ultraviolet
X-ray
Gamma ray

Question 12

Use of X-rays

Answer 12

X-rays can be used to observe the internal structure of objects. They are used for medical purposes to find out if patients have any broken bones.

Question 13

Gamma Rays Uses

Answer 13

Gamma rays can be used to sterilise food and surgical equipment by killing the microbes that live on them.

Question 14

Ultraviolet uses

Answer 14

Fluorescent materials absorb ultraviolet and emit the energy as visible light. This can be used for security marking on cars, check for forgeries and safety signs eg fire exits - visible in the dark.

Question 15

Similarities between light on the EM spectrum

Answer 15

All travel at the same speed in free space.

Question 16

Uses of visible light

Answer 16

Sight

Question 17

Ultraviolet effects

Answer 17

Exposure to UV light can lead the skin to tan, this darkens the skin to help protect it. Too much exposure can lead to sunburn, this is damaging of skin cells. It can also damage your eyes and cause blindness

Question 18

X-rays affects

Answer 18

• too much means cells can be damaged, mutated and destroyed. This can cause cancer.

Question 19

EM Ionising radiation

Answer 19

Ultraviolet, X-rays and gamma rays

Question 20

Protective measures for UV light

Answer 20

Suncream and sunglasses

Question 21

Protective measures for ionising radiation

Answer 21

Reduce exposure time.
Increase the distance between us and the source
Stand behind a lead screen

Question 22

Frequency of human hearing

Answer 22

20-20,000 Hz

Question 23

Loud equals….

Answer 23

High amplitude

Question 24

High pitch equals…

Answer 24

High frequency

Question 25

Low pitch equals…

Answer 25

Low frequency

Question 26

Quiet equals…

Answer 26

Low amplitude

Question 27

Large wavelength equals…

Answer 27

Low pitch

Question 28

Small wavelength equals…

Answer 28

High pitch

Question 29

What does the distance between the wavefronts represent?

Answer 29

The wavelength

Question 30

Doppler Effect

Answer 30

In front of the moving object the distances between the wavefronts decreases, the wavelength decreases and the frequency/pitch increases. Behind the moving object the distance between the wavefronts increases, the wavelength increases and the frequency/pitch decreases. Speed of the wave stays the same.

Question 31

Doppler Effect Explanation

Answer 31

It’s the change in the frequency or wavelength of a wave when the source of the wave is moving relative to the observer.

Question 32

How do X-rays work?

Answer 32

Expose your body to X-rays X rays are sent into the body Bones absorb the X-rays In soft tissues x rays are transmitted through When X-rays reach a photographic film X-rays turn the screen black and produce an image.