Waves, Light & Sound Quiz

Question 1

What is the difference between a transverse wave and a longitudinal wave?

Accepted Answer

In transverse waves, oscillations are perpendicular to the direction of travel; in longitudinal waves, they are parallel

Answer

Transverse waves travel faster

Answer

Longitudinal waves cannot travel through solids

Answer

Transverse waves require a medium; longitudinal waves do not

Question 2

What is the speed of sound in air at room temperature?

Accepted Answer

340 m/s

Answer

3,000 m/s

Answer

300,000 km/s

Answer

150 m/s

Question 3

What is refraction?

Accepted Answer

The bending of a wave as it passes from one medium to another due to a change in speed

Answer

The bouncing of a wave off a surface

Answer

The spreading of waves around obstacles

Answer

The absorption of wave energy

Question 4

What is the order of the electromagnetic spectrum from longest to shortest wavelength?

Accepted Answer

Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma

Answer

Gamma, X-ray, ultraviolet, visible, infrared, microwave, radio

Answer

Visible, radio, X-ray, microwave, infrared, ultraviolet, gamma

Answer

Radio, infrared, X-ray, visible, microwave, ultraviolet, gamma

Question 5

What is the law of reflection?

Accepted Answer

The angle of incidence equals the angle of reflection

Answer

The angle of incidence equals the angle of refraction

Answer

Waves always reflect at 90°

Answer

The reflected wave has less energy than the incident wave

Question 6

What type of electromagnetic radiation is used in mobile phone communications?

Accepted Answer

Microwaves

Answer

Infrared

Answer

X-rays

Answer

Ultraviolet

Question 7

What is the frequency of a wave that has a speed of 300 m/s and a wavelength of 0.5 m?

Accepted Answer

600 Hz

Answer

150 Hz

Answer

300 Hz

Answer

60 Hz

Question 8

What is diffraction?

Accepted Answer

The bending of waves around corners or through gaps

Answer

The splitting of white light into colours

Answer

The reflection of waves

Answer

The change in frequency when a source moves

Question 9

Which colour of visible light has the highest frequency?

Accepted Answer

Violet

Answer

Red

Answer

Yellow

Answer

Green

Question 10

What is the Doppler effect?

Accepted Answer

The apparent change in frequency of a wave when the source or observer is moving

Answer

The bending of light through a prism

Answer

The splitting of sound into echoes

Answer

The absorption of light by matter

Question 11

What is an echo?

Accepted Answer

A reflected sound wave heard after a short delay

Answer

Sound absorbed by soft surfaces

Answer

Sound that travels faster than normal

Answer

Interference between two sound waves

Question 12

What is total internal reflection?

Accepted Answer

When light hits a boundary at or beyond the critical angle and reflects entirely back into the medium

Answer

When all light is absorbed by a surface

Answer

When light passes straight through without bending

Answer

When a wave reflects off a flat mirror

Question 13

What does a converging (convex) lens do to parallel rays of light?

Accepted Answer

Brings them together at a focal point

Answer

Spreads them apart

Answer

Reflects them back

Answer

Absorbs them

Question 14

What causes the white light from the Sun to split into a rainbow of colours?

Accepted Answer

Refraction — different wavelengths of light slow down by different amounts in water/glass

Answer

Reflection off water droplets

Answer

Diffraction around clouds

Answer

Absorption and re-emission

Question 15

What is ultrasound?

Accepted Answer

Sound with frequency above 20,000 Hz, beyond human hearing

Answer

Very loud sound

Answer

Sound that travels faster than light

Answer

Electromagnetic waves used in hospitals

Question 16

What is the amplitude of a wave?

Accepted Answer

The maximum displacement of the wave from its rest position

Answer

The distance between two peaks

Answer

The number of waves per second

Answer

The speed of the wave

Question 17

Which type of electromagnetic radiation is most harmful to human DNA?

Accepted Answer

Gamma rays

Answer

Radio waves

Answer

Infrared

Answer

Visible light

Question 18

What is the critical difference between sound and light in terms of transmission?

Accepted Answer

Sound requires a medium to travel; light can travel through a vacuum

Answer

Light is faster than sound

Answer

Sound is a transverse wave; light is longitudinal

Answer

Light can only travel in straight lines

Question 19

What does the pitch of a sound depend on?

Accepted Answer

Frequency

Answer

Amplitude

Answer

Wavelength only

Answer

The medium it travels through

Question 20

What is optical fibre used for, and which physical principle does it rely on?

Accepted Answer

Transmitting light signals over long distances; using total internal reflection

Answer

Carrying electrical signals; using electrical resistance

Answer

Generating electricity; using the photoelectric effect

Answer

Filtering light; using diffraction