Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Waves
356 practice questions
Topics covered
Practice questions
321–330 of 356
Question 321
4 marks · Normal
Answer and see the solution →A laser sends light into an optical fibre at an angle of incidence of 72° to the normal. The critical angle for the core–cladding boundary is 60°.
(a)[2 marks]Explain whether the light will be totally internally reflected at the core–cladding boundary.
(b)[2 marks]If the refractive index of the core is 1.50, calculate the maximum refractive index of the cladding for total internal reflection to occur at this boundary. (Give your answer to 2 decimal places.)
Question 322
1 mark · Easy
Answer and see the solution →What type of wave are sound waves in air (longitudinal or transverse)?
Question 323
1 mark · Easy
Answer and check →Which of the following instruments can be used to see the shape of a sound wave?
- A.Oscilloscope
- B.Thermometer
- C.Barometer
- D.Stopwatch
Question 324
2 marks · Easy
Answer and see the solution →The speed of sound in air is 340 m/s. Calculate how long it takes a sound wave to travel 170 m. Give your answer in seconds.
Question 325
2 marks · Easy
Answer and see the solution →A sound wave is displayed on an oscilloscope screen. The time for one complete wave (time period) on the screen is 0.01 s. Calculate the frequency of the sound wave. State the correct unit.
Question 326
1 mark · Easy
Answer and see the solution →Sound waves cannot travel through a vacuum. Give a reason why.
Question 327
2 marks · Easy
Answer and see the solution →A microphone is connected to an oscilloscope showing a sound wave. The trace shows a high number of waves close together. What does this tell you about the pitch of the sound, and why?
Question 328
4 marks · Normal
Answer and see the solution →A drum is struck once to produce a sound in air. The drum's skin vibrates rapidly after being hit.
(a)[1 mark]State whether the sound wave produced by the drum is longitudinal or transverse.
(b)[2 marks]Explain how the sound travels from the drum to a listener's ear.
(c)[1 mark]Describe what would happen to the sound if the drum was played inside a vacuum.
Question 329
4 marks · Normal
Answer and see the solution →A student investigates the speed of sound in air using the echo method. She stands 120 m from a large wall. She claps her hands and starts a stopwatch when she sees the clap, stopping the watch when she hears the first echo. The time recorded is 0.7 seconds.
(a)[1 mark]Calculate the distance travelled by the sound wave from the student to the wall and back.
(b)[3 marks]Calculate the speed of sound in air in this experiment. Give your answer to 2 significant figures. Use the equation:
Question 330
3 marks · Normal
Answer and see the solution →You have a signal generator, a loudspeaker, a microphone and an oscilloscope. You want to find the frequency of a sound wave produced by the loudspeaker.
(a)[2 marks]Describe how you would use the oscilloscope to find the frequency of the sound.
(b)[1 mark]You observe that one complete wave on the oscilloscope trace takes 0.004 s. Calculate the frequency of the sound wave.