P2- Topic 6 - Waves 2022

Question 1

What are the two types of waves?

Answer 1

1. Transverse

2. Longitudinal

Question 2

What is a transverse wave and example ? 3

Answer 2

A wave for which the oscillations are
perpendicular to the direction of energy
transfer

Electromagnetic waves
Seismic s-waves

Question 3

What is a longitudinal wave? and example 3

Answer 3

A wave for which the oscillations are
parallel to the direction of energy
transfer

Sound waves
Seismic p-waves

Question 4

Why is the wave and not
the water or air itself that travels.
3

Answer 4

all waves trasnsfer energy from one place to another

rippels transfer kinetic energy

sound waves transfer sound energy

Question 5

What are the two parts of a longitudinal wave called?

Answer 5

Compressions and rarefactions

Question 6

What is a wave’s amplitude?

Answer 6

distance from equilibrium line to the maximum displacement (crest or trough) .

Question 7

What is wavelength?2

Answer 7

distance between the same points on two consecutive waves

peak to peak or trough to trough

Question 8

What is the frequency of a wave?

Answer 8

The number of waves that pass a given
point each second

1Hz= 1 wave per second

Question 9

What is the unit used for frequency?

Answer 9

Hertz, Hz

Question 10

What is wave speed?

Answer 10

the speed at which the energy is transferred (or

the wave moves) through the medium.

Question 11

how to calculate the period of one wave?

Answer 11

period = 1÷frequency
T =1÷f
Period(s) frequency(Hz)

Question 12

State the equation used to calculate wave speed.

Give appropriate units
2

Answer 12

Wave Speed =
Frequency x Wavelength

Speed (m/s),
Frequency (Hz),
Wavelength (m)

Question 13

What word is used to describe when a wave

bounces off a surface?

Answer 13

Reflection

Question 14

describe a method to measure the speed of sound waves in

air 3

Answer 14

Make a noise at ~50m from a solid wall, and record time for the echo to be heard,
then use speed = distance/time

Have two microphones connected to a datalogger at a large distance apart, and

record the time difference between a sound passing one to the other – then use
speed = distance/time

Question 15

describe a method to measure the speed of ripples on a water

surface 3

Answer 15

Use a stroboscope, which has the same frequency as the water waves

measure distance between the ‘fixed’ ripples and use
𝑣 = 𝑓/⁁

Move a pencil along the paper at the same speed as a wavefront, and measure the time taken to draw this line – then use speed = distance/

Question 16

What is a Reflected ray on different surfaces

Answer 16

Waves will reflect off a flat surface

• The smoother the surface, the stronger the reflected wave is
• Rough surfaces scatter the light in all directions, so they appear
  matt and not reflective.

Question 17

What is a transmission wave on different materials

Answer 17

Waves will pass through a transparent material

• The more transparent, the more light will pass through the material
• It can still refract, but the process of passing through the material and still emerging is
  transmissio

Question 18

What is absorption of a wave on different materials 2

Answer 18

waves are absorbped by the material the wave is trying to get into

tramsfers the energy to the materials energy strores

Question 19

what does the angle of incidence equal

Answer 19

the angle of reflection

Question 20

What is the frequency range of human hearing?

Higher

Answer 20

20 Hz - 20kHz

Question 21

what is the effect on sound waves on an eardrrum 3

Answer 21

sound waves hit the
eardrum

compression forces ear inward, rarefraction outward by pressure

sound waves cause the ear drum and other parts of the inner ear to vibrate

causing sound

Question 22

why such processes only work over a limited

frequency range and the relevance of this to human hearing. 2

Answer 22

works over limited frequency range as the normal human hearing is 20Hz to 20kHz

frequenecies outside this range may not be able to cause the eardrum to vibrate

Question 23

How do sound waves travel through a solid?

Answer 23

The particles in the solid vibrate and
transfer kinetic energy through the
material.

Question 24

causes of limitations to the ear 4

Answer 24

cochlea= hairs attuned to the higher frequencies die or get damaged.

constant loud noise damaging these hairs over the years

changes in the inner ear as you grow older

o Smoking, chemotherapy, diabetes

o So higher frequencies cannot be heard as we get older

Question 25

What are ultrasound waves?

Answer 25

Waves which have a frequency higher
than the upper limit of human hearing
(20kHz)

Question 26

Give an example use for ultrasound waves?2

Answer 26

Medical or industrial imaging.

pregnancy scan

Question 27

What natural event causes seismic waves to be produced? What types are
produced? 3

Answer 27

● Earthquakes
● They produce both P-waves and
S-waves

Question 28

State a difference between the mediums that P-waves and S-waves can travel through. 2

Answer 28

● P-waves travel through both solids and liquids
● S-waves only travel through solids
(not liquids)

Question 29

What technique is used to detect objects in deep water and measure water depth? 4

Answer 29

● Echo sounding
● High frequency sound waves are emitted,
reflected and detected
● Time difference between emission and detection,
alongside wave speed, are used to calculate
distances

Question 30

What type of spectrum do

electromagnetic waves form?

Answer 30

A continuous spectrum

Question 31

Order the types of electromagnetic radiation from lowest to highest frequency.
7

Answer 31

Radio waves
● Microwaves
● Infrared
● Visible Light
● Ultraviolet
● X-rays
● Gamma Rays

Question 32

How do the speeds of EM radiation differ

in a vacuum and in air?

Answer 32

Electromagnetic waves all travel at the

same speed in a vacuum and in air.