Waves

Question 1

The wave below has a frequency of 14 Hz.
Calculate the speed of this wave.

Answer 1

v = f x λ
v = 14 x 0.10
v = 1.4 ms^-1

NOTE the conversion of cm -> m!

Question 2

What type of wave are microwaves an example of - transverse or longitudinal?

Answer 2

Microwaves are an example of transverse waves.

Question 3

Name the three quantities shown in this formula.

Answer 3

v = speed

f = frequency

λ = wavelength

(the λ symbol is called ‘lambda’)

Question 4

What type of wave is a water wave an example of?

Answer 4

A water wave is an example of a transverse wave.

Question 5

Name the three quantities shown in this formula.

Answer 5

d = distance

v = speed

t = time

Question 6

How would km (kilometres) be converted into metres?

Answer 6

k (kilo) = x 1000
To convert km –> m, ** multiply by 1000**

Question 7

Explain why sound cannot travel through a vacuum.

Answer 7

A vacuum is empty space - there are no particles in a vacuum.
For sound to travel, there must be particles that vibrate to transmit the sound waves.

Question 8

What is meant by the frequency of a wave?

Answer 8

Frequency is the number of waves per second.

Question 9

What type of wave is a sound wave an example of?

Answer 9

A sound wave is an example of a longitudinal wave.

Question 10

What is the unit for distance?

Answer 10

The unit for distance is metres (m)

Question 11

24 waves are produced in 8 seconds.
What is the frequency of the waves?

Answer 11

24 / 8 = 3 Hz

(24 waves in 8 seconds
so 3 waves in 1 second)

Question 12

What is the unit for amplitude?

Answer 12

The unit for amplitude is metres (m).

Question 13

The wave below has a frequency of 5 Hz.
Calculate the speed of this wave.

Answer 13

v = f x λ
v = 5 x 3
v = 15 ms^-1

Question 14

What is the amplitude of this wave?

Answer 14

0.7 m
(the amplitude is measured from middle to top of wave)

Question 15

Water waves pass a harbour wall with a frequency of 4 Hz.
How many waves will pass the wall in 1 minute?

Answer 15

4 Hz = 4 waves per second
In 1 minute, there will be 60 x 4 = 240 waves.

Question 16

What is the unit for time?

Answer 16

The unit for time is seconds (s).

Question 17

Name an example of a longitudinal wave.

Answer 17

Sound waves are longitudinal waves.

Question 18

Complete the following sentence:

All waves carry ……………

Answer 18

All waves carry energy.

Question 19

What is meant by the wavelength of a wave?

Answer 19

Wavelength is the distance between a point on one wave and the same point on the next wave.

Question 20

What can sound travel through?

Answer 20

Sound can travel through
* solid
* liquid
* gas

Question 21

What is the unit for frequency?

Answer 21

The unit for frequency is hertz (Hz).

Question 22

What is meant by the statement “A frequency of 16 Hz” ?

Answer 22

This means that there are 16 waves per second.

Question 23

From the diagram shown, identify the amplitude of the wave.

Answer 23

D is the amplitude.

Question 24

What is meant by the amplitude of a wave?

Answer 24

The amplitude of a wave is the height of the wave, measured from middle to top.

Question 25

What is the unit for wavelength?

Answer 25

The unit for wavelength is metres (m).

Question 26

From the diagram shown, identify the wavelength of the wave.

Answer 26

C is the wavelength.

Question 27

What is the wavelength of this wave?

Answer 27

6 m

Question 28

True or False :
“Sound can travel through space”

Answer 28

FALSE
Space is a vacuum and sound cannot travel through a vacuum

Question 29

A loudspeaker emits sound with a frequency of 500 Hz.
Explain this sentence in your own words.

Answer 29

There are 500 waves produced per second.

Question 30

What is the wavelength of this wave?

Answer 30

1.2 m

Question 31

How would cm (centimetres) be converted into metres?

Answer 31

100 cm = 1 m
To convert cm –> m, divide by 100

Question 32

What is the unit for speed?

Answer 32

The unit for speed is metres per second (ms^-1).