Topic 3 - Waves (GCSE Edexcel Combined Physics Retrieval Questions)

What is a wave?

A wave is a way of transferring energy or information without the transfer of matter

Define frequency.

The number of waves passing a point per second.

Define wavelength.

The distance between a point on one wave and the same point on the next wave

Define amplitude.

The maximum displacement of a point of a wave from its rest position.

Define time period.

The time taken for one complete oscillation to occur

What is the definition of a longitudinal wave?

An oscillation traveling parallel to the direction of energy transfer.

What is the definition of a transverse wave?

An oscillation traveling perpendicular to the direction of energy transfer.

What do waves transfer?

Energy

Give the equation linking time period and frequency

Time Period = 1/Frequency

What is the unit of frequency?

Hertz (Hz)

What is the unit of time period?

seconds (s)

Give the equation linking wave speed, frequency and wavelength.

Wave Speed = Frequency x Wavelength

What is the unit of wave speed?

meters/second (m/s)

What is the unit of wavelength?

meters (m)

Are electromagnetic waves longitudinal or transverse?

Transverse

Are sound waves longitudinal or transverse?

Longitudinal

What speed do electomagnetic waves travel in a vacuum?

300,000,000m/s

How do you find the wavelength in the wave speed of a liquid core practical?

Measure length of 10 waves and divide by 10.

What is the law of reflection?

Angle of incidence is equal to angle of reflection

What is the definition of refraction?

When a wave changes direction as it crosses a boundary

What happens when a light wave travels from air to glass (speed and direction)?

The light wave slows down and bends towards the normal

How do you draw the normal?

At 90° to the boundary

Where do you measure the angle of incidence?

Between the incident ray and the normal

Where do you measure the angle of reflection?

Between the reflected ray and the normal

Where do you measure the angle of refraction?

Between the refracted ray and the normal

If you refract white light through a prism, which colour refrects the least and why?

Red because it has the lowest wavelength.

List the electromagnetic spectrum in order of increasing wavelength

Gamma, x-rays, ultra-violet, visible light, infra-red, microwaves, radio waves

List the electromagnetic spectrum in order of increasing frequency

Radio waves, microwaves, infra-red, visible light, ultra-violet, x-rays, gamma

Give two uses of radio waves

Broadcasting and communication

Give two uses of microwaves

Cooking and satellite transmissions

Give two uses of infra-red radiation

Heaters and night-vision equipment

Give two uses of visible light

Photography and optical fibres

Give one use of ultra-violet radiation

Fluorescent lamps to show up security markings

Give two uses of x-rays

Observing inside objects (airport security) and imaging inside the human body (medical applications)

Give two uses of gamma radiation

Cancer treatment and sterilising medical equipment

Give a danger of microwaves

Internal heating of body tissue

Give a danger of infra-red radiation

Skin burns

Give two dangers of gamma radiation

Cancer, mutations to cells

Give two dangers of ultra-violet radiation

Skin cancer, blindness

Which electromagnetic waves are ionising?

Gamma, X-Rays and Ultra-Violet

How are radio waves produced?

Radio waves can be produced by oscillations in electrical circuits.

How are gamma rays produced?

Gamma rays are produced by changes in the nucleus of an atom.