Waves

Question 1

What is a wave?

Answer 1

It is the propagation of a disturbance created in a medium away from its source

Question 2

What is the purpose of a wave?

Answer 2

To transfer energy

Question 3

What are the 2 types of waves?

Answer 3

Transverse waves and Longitudinal waves

Question 4

What is a transverse wave?

Answer 4

It is a wave in which the molecules vibrate perpendicular to the direction of the wave

Question 5

What is a longitudinal wave?

Answer 5

It is a wave in which the molecules vibrate parallel to the direction of the wave

Question 6

What are the differences between a transverse and a longitudinal wave?

Answer 6

A longitudinal wave consists of alternate regions of compression and rarefaction and the particles vibrate parallel to the direction of the wave, while a transverse wave consists of alternate crests and troughs and the particles vibrate perpendicular to the direction of the wave

Question 7

What is amplitude?

Answer 7

The maximum displacement of the molecules from the undisturbed surface

Question 8

What is displacement?

Answer 8

It is the distance moved by the particles of a medium from the undisturbed surface

Question 9

What is the time period?

Answer 9

It is the time taken to complete one wave

Question 10

What is frequency and the formula and unit?

Answer 10

It is the number of waves completed in 1 second. F = 1/T. Hz

Question 11

What is wavelength?

Answer 11

It is the horizontal distance between 2 consecutive crests/troughs

Question 12

Formula to measure the speed of a wave

Answer 12

V = F(lamda)

Question 13

What is the wavefront?

Answer 13

It is a line along which all particles are at their maximum displacement

Question 14

What are the different type of wavefronts?

Answer 14

Parallel and Circular

Question 15

What is the distance between two consecutive wavefronts?

Answer 15

The wavelength

Question 16

Purpose of a vibrator in a ripple tank?

Answer 16

Used to produce disturbance in water

Question 17

Purpose of the white screen in a ripple tank setup

Answer 17

To observe the image of the wave pattern

Question 18

Purpose of elastic band in a ripple tank

Answer 18

It controls the up and down movement of the vibrator

Question 19

How do you produce parallel wavefronts in a ripple tank?

Answer 19

A sharp metal strip is connected below the vibrator. When the vibrator is switched on, parallel wavefronts are seen on the white screen and they keep shifting away from the vibrator

Question 20

How do you produce circular wavefronts in a ripple tank?

Answer 20

A metal sphere is connected below the vibrator. When the vibrator is switched on, circular wavefronts are seen on the white screen and they move away from the vibrator

Question 21

How do you demonstrate reflection of parallel waves in a ripple tank?

Answer 21

A metal barrier is placed a short distance from the vibrator in an inclined position. When the vibrator moves up and down, wavefronts are seen to move towards the barrier and also away from the barrier in another direction. This shows reflection has taken place

Question 22

How you do demonstrate refraction of parallel wavefronts in a ripple tank? (4)

Answer 22

1) Two regions (deep and shallow) are created by placing a plastic sheet a short distance away from the vibrator.
2) When the vibrator is switched on, parallel wavefronts of constant wavelength will be produced.
3) When the wavefronts travel in the shallower region, the wavefronts are seen to be closer.
4) This means that velocity has decreased and therefore refraction has taken place.

Question 23

How do you convert KHz to Hz?

Answer 23

1KHz —-> 1000KHz

Multiply by 1000