The Properties of Waves

Question 1

What is the Amplitude?

Answer 1

The Maximum displacement of a point on the wave from its undisturbed position

Question 2

Wavelength definition -

Answer 2

Wavelength - the distance from a point on the wave to the equivalent point on the adjacent wave

Question 3

Frequency definition -

Answer 3

The number of waves passing a fixed point every second

Question 4

what is the equation that links period and frequency?

Answer 4

Period(s) = 1/ frequency (Hz)

Question 5

What is the wave speed?

Answer 5

The distance travelled by each wave in a given amount of time

Question 6

What is the equation that links wave speed, frequency and wavelength?

Answer 6

Wave speed (m/s) = frequency (Hz) x wavelength (m)

Question 7

What does a bigger amplitude mean?

Answer 7

The more energy the wave carries

Question 8

At the boundary between two material, light can be one the the 3 things:

Answer 8

• Reflected
• Transmitted ( this includes being Refracted)
• Absorbed

Question 9

Angle of incident =

Answer 9

angle of reflection

Question 10

Where are waves reflected

Answer 10

At different boundaries

Question 11

What are the different ways the waves can be reflected

Answer 11

• Specular reflection
• Diffuse reflection

Question 12

What is specular reflection

Answer 12

When a wave is reflected in a singular direction by a smooth surface e.g when light is reflected by a mirror you get a clear reflection

Question 13

what is a diffuse reflection

Answer 13

When a wave is reflected by a rough surface
E.g. a piece of paper and the reflected rays are scattered in lots of directions

Question 14

Why do diffuse reflection happen

Answer 14

Because the surface is not smooth so the normal is different for each incoming ray, which means the angle of incidence is difference for each ray

Question 15

What happened when light is reflected by a rough surface

Answer 15

The surface appears matte and you don’t get clear reflection of objects

Question 16

What is a transverse wave

Answer 16

The oscillations are perpendicular to the direction of energy transfer

Question 17

Name 4 examples of a transverse wave

Answer 17

• electromagnetic waves
• seismic S-waves
• ripples and waves in water
• light

Question 18

What is a longitudinal wave

Answer 18

oscillations are parallel to direction of energy transfer

Question 19

name 3 examples of longitudinal waves

Answer 19

• sound waves
• ultrasound
• seismic P-waves

Question 20

What are the 2 main types of waves

Answer 20

-Mechanical waves
- Electromagnetic waves

Question 21

What are mechanical waves

Answer 21

Waves that vibrate through a medium e.g. sound

Question 22

What are electromagnetic waves

Answer 22

Waves that can travel through a vacuum (no medium is needed) e.g. light

Question 23

All electromagnetic waves are transverse / longitudinal

Answer 23

Transverse

Question 24

What are sound waves

Answer 24

Sound waves are vibrations that travel through a medium

Question 25

How are sound waves caused

Answer 25

• vibrating objects
• vibration are passed to the surrounding medium as a series of compressions and rarefactions

Question 26

How do you hear sound

Answer 26

• sound waves make your ear drum vibrate
• vibrates passed onto tiny bones in your ear called ossicles, through semicircular canals and to the cochlea
• cochlea turns these vibrations into electrical signals which was sent to the brain

Question 27

What is the hearing range for a human

Answer 27

20 Hz - 20kHz

Question 28

What is ultrasound?

Answer 28

Ultrasound are sound waves above the frequency of 20kHz

Question 29

what are the uses for ultrasound

Answer 29

• pre-natal scanning
• medical uses( skin burns)
• clean jewelry

Question 30

what happened when ultrasound reaches a boundary

Answer 30

• they are partially reflected so some of the ultrasound waves are reflected at the boundary, and some are transmitted(refracted)
• time taken for the waves to reflect ( leave a source and return to a detector ) is measured
• time it takes to reflect back to the detector can measure thedepth of the boundary