P5 - Waves in matter

Question 1

Define Amplitude

Answer 1

The distance from the undisturbed rest position to the peak or trough of a wave.

Question 2

Define Wavelength, and how it’s different between longitudinal waves and transverse waves

Answer 2

The distance from one point on the wave to the same point on the next wave.

Transverse wave:
- The wavelength can be measured from one peak to the next peak.

Longitudinal wave:
- The wavelength can be measured from the centre of one compression to the centre of the next.

Question 3

Wavelength symbol

Answer 3

λ (Lambda)

Question 4

Define Frequency

Answer 4

The number of waves passing a point in a second.

Question 5

Define time period

Answer 5

• The time taken for a single wave to pass a point.

Question 6

Equation for time period

Answer 6

T = 1/f

Question 7

Equation for wave speed

Answer 7

• Wave speed = Frequency x Wavelength
• v = f x λ

v = wave speed in metres per second (m/s)
f = frequency in Hertz (Hz)
λ = wavelength in metres (m)

Question 8

Equation for frequency

Answer 8

f = 1/T

Question 9

Define waves

Answer 9

• Waves are repeated oscillations that transfer energy.

Question 10

Define transverse waves

Answer 10

• Waves where the direction of vibrations and energy transfer is perpendicular to the direction of travel of the wave.

Question 11

Define longitudinal waves

Answer 11

• Waves where the direction of vibrations and energy transfer is the same as the direction of the wave.

Question 12

Law of incidence

Answer 12

Angle of incidence = angle of reflection

Question 13

What happens when light enters a ‘less optically dense’ material?

Answer 13

• The light will speed up.
• The light is refracted further away from the normal.

Question 14

What happens when light enters a ‘more optically dense’ material?

Answer 14

• The light slows down.
• The light is refracted closer to the normal.