Unit 2.4: The Nature of Waves

Question 1

What is a Progressive wave?

Answer 1

A progressive wave is a pattern of disturbances travelling through a medium and carrying energy, involving the the particles of the medium oscillating about their equilibrium position.

Question 2

The transfer of what is not involved with Progressive waves?

Answer 2

The transfer of matter.

Question 3

There are 2 types of progressive waves, name them.

Answer 3

Longitudinal and transverse

Question 4

What is a transverse wave?

Answer 4

The oscillations of the particles are at right angles to the direction of travel of the wave

Question 5

Define a longitudinal wave.

Answer 5

The oscillations of the particles are in parallel with the direction of travel of the wave

Question 6

Give one example of both progressive waves

Answer 6

Light(Transverse) and Sound(Longitudinal)

Question 7

Define wavelength

Answer 7

The minimum distance between 2 points on the wave oscillating in phase

Question 8

Define frequency

Answer 8

The number of cycles of a wave passing a given point every second

Question 9

Define amplitude

Answer 9

Distance from the middle of the wave to the crest

Question 10

Define speed of a wave

Answer 10

The distance travelled by the wave in 1 second

Question 11

Define the term ‘Phase’

Answer 11

The relationship between the pattern of vibration of two points on a wave

Question 12

What is Phase difference?

Answer 12

The difference in position of 2 points within a cycle of oscillation

Question 13

Points which are oscillating in______ will be multiples of 360°

Answer 13

phase

Question 14

Points which are oscillating in_____will be multiples of 180°

Answer 14

anti-phase

Question 15

What is a polarised wave?

Answer 15

A polarised wave is a transverse wave in which particle oscillations occur in only one of the directions at right angles to the direction of wave propagation

Question 16

Do domestic light bulbs and the sun emit
polarised or unpolarised light?

Answer 16

unpolarised

Question 17

What is the difference between unpolarised light and polarised

Answer 17

With unpolarised ligtht the vibrations take place in many directions, instead of in the single plane associated with plane-polarised ratiation

Question 18

What does a polaroid lens do?

Answer 18

A polaroid lens allows
oscillations in only one
direction to pass through,
the other directions are
absorbed.

Question 19

What happens if you try to view plane polarised light through a second sheet of polaroid at right angles to each other?

Answer 19

If the polarised lenses are at right angles to each other,it will be found that the intesnity of light passing through will be 0.