Waves can either be transverse or longitudinal
Compare transverse and longitudinal waves.
Figure 1 shows a longitudinal wave.
Figure 1
Label Figure 1, to show clearly what is meant by the terms:
Compression Rarefaction
Figure 2 below shows a duck floating on the surface of a pond.
Figure 2
As waves pass beneath the duck, they cause the duck to move.
Draw arrows on Figure 2 showing the direction in which the duck will move.
Did this page help you?
A low-frequency sound wave received by a microphone is represented as a transverse wave on an oscilloscope.
Figure 1 shows a transverse wave's displacement against time.
Figure 1
Calculate the frequency of this wave and give the units.
Frequency = .................................... Units: ..............
Determine the amplitude of the wave in Figure 1.
Amplitude = .................................... m
Higher Tier Only
Complete the bullet points.
Choose answers from the box.
Each answer can be used once, more than once or not at all.
higher | lower | the same |
A higher-pitched sound at the same volume would have:
.............................. frequency
.............................. amplitude
A louder sound at the same pitch would have:
.............................. frequency
.............................. amplitude
Explain why the sound wave in Figure 1 is not audible to humans.
Did this page help you?
Water waves are passing a buoy floating out at sea in Figure 1.
Figure 1
It takes 2 minutes for 10 complete surface waves to pass the buoy.
Calculate the period of one wave.
Period = .................................... s
Calculate the frequency of the waves.
Give your answer to 2 significant figures.
Frequency (2 significant figures) = .................................... Hz
The buoy is 150 m from the shore.
A lifeguard counts 12 waves between the buoy and the shore at any one time.
Calculate the speed of the waves.
Give your answer to 2 significant figures.
Wave speed (2 significant figures) = ............................. m/s
The wind picks up and the wave speed doubles.
The wavelength remains the same.
Describe how this will affect the frequency.
Did this page help you?
Two girls stand some distance away from a wall and clap two wooden blocks together. The sound from the blocks reflects from the wall, producing an echo.
They then continue to clap the blocks together, timing each clap so it is in time with each echo.
This is shown in Figure 5 below:
Figure 5
Plan how they can use the above method to determine the speed of sound, stating clearly what measurements they must take.
The girls estimate the speed of sound to be 340 m / s.
The sounds they produce have an average frequency of 1020 Hz.
Calculate the wavelength of the sound waves.
Did this page help you?
A student lights a candle and places it in front of a mirror.
The student can see an image of the candle flame in the mirror. This is represented in Figure 6 below.
Figure 6
Complete the ray diagram in Figure 5 above, showing how the image is formed.
Mark the position of the image.
The image is virtual.
What is a virtual image?
Did this page help you?
Higher Tier Only
When sound waves enter the human ear, they encounter the eardrum and cause it to vibrate.
Describe the process by which the sound waves cause the eardrum to vibrate.
Higher Tier Only
Figure 7 below shows a ship using an echo sounder to measure the depth of the water.
Figure 7
The echo sounder produces short bursts of ultrasound.
What is ultrasound?
Higher Tier Only
The ultrasound pulse travels through the water at a speed of 1500 m/s.
A period of 320 milliseconds passes between a pulse being emitted and received by the echo sounder.
Calculate the depth of the water.
Higher Tier Only
Ultrasound is also used in medicine to scan prenatal babies.
Explain why X-rays can also be used to image the body, but are not used to scan prenatal babies.
Did this page help you?
Higher Tier Only
Earthquakes produce two different types of seismic waves: P-waves and S-waves.
Identify the relevant words below by drawing a circle to indicate the nature of both P-waves and S-waves.
P-waves: | Transverse | Longitudinal |
S-waves: | Transverse | Longitudinal |
P-waves travel with an average speed of about 7000 m/s.
Some P-waves are produced by a minor earthquake and detected a short while later by a seismometer 3000 km away.
Calculate how long it will take the P-waves to reach the seismometer.
Higher Tier Only
Figure 7 below shows S-waves passing through the internal structure of the Earth.
Figure 7
Whilst S-waves can be detected on the side of the Earth nearest to an earthquake, they cannot be detected on the opposite side.
Explain what this tells us about the internal structure of the Earth.
Did this page help you?
On a beach popular with surfers, one is watching a buoy move up and down with the waves, in Figure 1.
Figure 1
She decides to plot a graph of how the height of the buoy varies with time - this is Figure 2.
Figure 2
Using a stopwatch, she measures the time from the buoy at its highest point to the peak of the 7th and smallest wave.
This takes 24.5 s.
Calculate the frequency of the waves.
Give your answer to 2 significant figures.
Frequency (2 significant figures) = .................................... Hz
The surfer knows the distance to the buoy from the shore.
Describe a method by which the surfer could determine the speed of the waves accurately.
The surfer determines that the wave speed is a value between 3.5 m/s and 4.5 m/s.
Calculate the possible range of wavelengths of the waves.
Give your answers to 2 significant figures.
Wavelength is between ........................ m and .................. m
Suggest why the surfer could only give a range of values for wave speed.
Did this page help you?
Students in a classroom are trying to calculate the speed of different waves along a string. The equipment provided is shown in Figure 1.
Figure 1
Plan an experiment, using the equipment in Figure 1, that would allow the students to determine the wave speed of different waves along the string.
The students double the frequency each time they perform the experiment and sketch the waves they observe. These sketches are shown in Figure 2.
Figure 2
One of the students makes the conclusion:
"The frequency is doubling so the speed must also be increasing".
Explain why this statement is incorrect.
The students finish early and start a second experiment to study the effect of varying tension force in the string.
They add mass to the end of the string and vary the frequency until they produce the following wave on the string:
Figure 3
They then add more mass and change the frequency until the pattern from Figure 3 appears again.
They then determine the tension and wave speed at each wave speed.
Identify the dependent and independent variables in their experiment.
Name the variable the students must control in this second experiment.
Did this page help you?
Higher Tier Only
Figure 1 shows an ultrasonic transmitter and receiver being used to detect cracks in steel rails. The transmitted and reflected pulses are shown on an oscilloscope's screen below.
The oscilloscope time base measures 10 microseconds per division on the horizontal axis.
Figure 1
Explain why there are two reflected pulses for transmitter B on the right.
Higher Tier Only
The speed of the ultrasound wave in steel is 6000 m/s.
Calculate the thickness of the steel.
Thickness = .................................... m
Higher Tier Only
Calculate the depth of the crack as a percentage of the thickness of the steel.
Percentage depth of the crack = .................................... %
Did this page help you?