P6 Waves

What is a transverse wave? (2)

a wave that oscillates at right angles (perpendicular) to the direction it is travelling.

they can travel through a vacuum

What is a longitudinal wave? (2)

a wave that oscillates in the same direction (parallel) as the direction it is travelling

they can only travel through a medium

What is an example of a transverse wave?

Water waves (ripples)
Light

What is an example of a longitudinal wave?

Sound waves

What is the difference between longitudinal and transverse waves?

Longitudinal waves osciallate parallel to the direction of energy transfer. Transverse waves oscillate perpendicular to the direction of energy transfer.

Are water ripples examples of a transverse or a longitudinal wave?

Transverse

Is sound an example of a transverse or a longitudinal wave?

Longitudinal

What is the definition for the amplitude of a wave?

the maximum displacement of a point on a wave away from its undisturbed position

What is the definition for the wavelength of a wave?

the distance from a point on one wave to the same point on the next wave

What is the definition for the frequency of a wave?

the number of waves passing a point each second

What is the definition for the time period of a wave?

the time taken for a wave to complete one full oscillation

What is the equation that links time period and frequency of a wave?

Period = 1 / frequency

What is the unit for time period?

seconds, s

What is the unit for frequency?

Hertz, Hz

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

wave speed = frequency x wavelength

What is the unit for wave speed?

metres per second, m/s

What is the unit for wavelength?

metres, m

Describe a method to measure the speed of sound waves in air (4)

Make a loud noise on a field near a wall

Use a measuring tape to measure the distance to and from the wall

Use a stopwatch to measure the time for the echo of the noise to be heard

Use the equation: speed = distance / time to calculate the speed of the sound waves

Describe a method to measure the speed of ripples on water (4)

Set up a ripple tank

Use a ruler to measure wavelength

Use a stopwatch to measure frequency

Use the equation wave speed = frequency x wavelength to calculate the speed

What are electromagnetic waves?

transverse waves that transfer energy from the source of the waves to an absorber

What are the waves on the electromagnetic spectrum, in order from longest to shortest wavelength? (7)

Radio

Microwaves

Infrared

Visible light

Ultraviolet

X-rays

Gamma rays

Which part of the electromagnetic spectrum transfers the most energy?

Gamma rays

Which part of the electromagnetic spectrum has the shortest wavelength?

Gamma rays

Which part of the electromagnetic spectrum has the highest frequency?

Gamma rays

Which part of the electromagnetic spectrum has the longest wavelength?

Radio waves

Which part of the electromagnetic spectrum has the smallest frequency?

Radio waves

What happens when a wave refracts?

It changes direction

What type of surfaces are good at absorbing and emitting raditation?

Dark, matte (dull) coloured surfaces

What type of surfaces are good at reflecting radition?

Bright, shiny coloured surfaces

How can gamma rays be produced?

by changes in the nucleus of an atom

Which types of waves can have hazardous effects on body tissue? (3)

ultraviolet waves

X-rays

gamma rays

What is radiation dose (in Sieverts) a measure of?

the risk of harm resulting from an exposure of the body to radiation

What are the risks of ultraviolet waves on body tissue? (2)

can cause skin to age prematurely

can increase the risk of skin cancer

What are the risks of X-rays and gamma rays on body tissue?

they are ionising radiation that can cause the mutation of genes and cancer

What are uses of radio waves?

Television and radio

What are uses of microwaves? (2)

Satellite communications

cooking food

What are uses of infrared? (3)

Electrical heaters

cooking food

infrared cameras

What are uses of visible light?

Fibre optic communications

What are uses of ultraviolet?

Energy efficient lamps, sun tanning

What are uses of X-rays? (2)

medical imaging

treatments (e.g. treating cancer)

What are uses of gamma rays? (2)

medical imaging

treatments (e.g. treating cancer)