Waves

Question 1

period

Answer 1

period = 1 / frequency

T = 1 / f

Question 2

velocity

Answer 2

velocity = frequency x wavelength

v = fλ

Question 3

What is meant by a transverse wave?

Answer 3

A transverse wave is a wave in which the oscillations (vibrations) are perpendicular to the direction that the wave travels.

Question 4

Give 3 examples of transverse waves.

Answer 4

Examples of transverse waves are:
Light and all other electromagnetic waves,
Ripples on water,
Waves on strings when wiggled up and down.

Question 5

What is a longitudinal wave?

Answer 5

Longitudinal waves are waves in which the oscillations (vibrations) are parallel to the direction the wave travels.

Question 6

State 2 examples of longitudinal waves.

Answer 6

Examples of longitudinal waves are:
Sound waves,
A spring when you push the end.

Question 7

What is meant by areas of compression and rarefaction in a longitudinal wave?

Answer 7

In areas of compression, the particles are bunched up close together. In areas of refraction, the particles are more spread out.

Question 8

Describe what is meant by a wave.

Answer 8

A wave is an oscillation (vibration) that transfers energy without transferring any matter.

Question 9

Describe what happens when waves travel through a medium.

Answer 9

When waves travel through a medium, the particles of the medium oscillate and transfer energy between each other, but the particles stay in the same place. Only energy is transferred.

Question 10

Waves transfer energy but not matter. Give an example of this.

Answer 10

If you strum a guitar and create sound waves, these waves don’t carry air away from the guitar to create a vacuum.

Question 11

Do water waves cause water molecules to travel across the water’s surface? Describe an observation which supports this.

Answer 11

No. An object will Bob up and down on the ripples rather than move across the water.

Question 12

What is the amplitude of a wave?

Answer 12

The amplitude of a wave is the maximum displacement of a point on the wave from its undisturbed (rest) position.

Question 13

What is the wavelength of a wave?

Answer 13

The wavelength is the distance between the same point on two adjacent waves.

Question 14

What is the frequency of a wave?

Answer 14

The frequency is the number of waves passing a certain point per second.

Question 15

What is the period of a wave?

Answer 15

The period is the time taken for one cycle of a wave to be completed.

Question 16

A wave has a frequency of 4.0 x 10^7 Hz and a speed of 3.0 x 10^8 m/s. Find it’s wavelength.

Answer 16

v =  λf
λ = v / f

λ = (3.0x10^8) / (4.0x10^7) = 7.5 m

Question 17

A buoy measures the frequency of an ocean wave as 0.2 Hz. Calculate the period of the wave.

Answer 17

T = 1/f
T= 1/0.2 
T = 5 seconds

Question 18

What is meant by the term ‘wave speed’ ?

Answer 18

A wave’s speed is the speed at which energy is being transferred (or the speed the wave is moving at).

Question 19

Describe a way of measuring the speed of sound in air.

Answer 19

Try to concisely write this another time, too tired now.

Question 20

What is the approximate speed of sound in air?

Answer 20

The average speed of sound in air is around 330 m/s.

Question 21

A wave is generated on a taut string using a vibration transducer. Describe how the speed of the waves on the string can be measured.

Answer 21

ITS TOO LATE FOR THIS IDEK ILL DO IT TOMORROW

Question 22

Calculate the speed of a wave with a wavelength of 0.45m and a frequency of 15 Hz.

Answer 22

v = f λ
v = 15 x 0.45 
v = 6.75 m/s