Quick answer: Sound is a longitudinal wave of compressions and rarefactions that needs a medium to travel through. This Physics 9-10 test on sound waves has 8 questions worth 20 marks, to do in 45 minutes: hearing range, thunder and sonar. The mark scheme is on a separate page; free printable PDF.
Answer all questions. Show your working, and give units. Use 330 m/s for the speed of sound in air unless the question states another value. A calculator is allowed. The test is out of 20 marks.
Level: Physics grades 9-10 (GCSE · IGCSE · O Level · Class 9-10) · Curriculum: IGCSE 3.4
Question 1 Hearing range (2 marks)
- State the approximate range of frequencies that a healthy young person can hear. (1 mark)
- State what is meant by ultrasound. (1 mark)
Question 2 Thunder (3 marks)
Kofi hears thunder 6.0 s after seeing lightning. The speed of sound in air is 330 m/s. Calculate the distance to the lightning. (3 marks)Question 3 Sonar (3 marks)
A ship sends a pulse of ultrasound to the seabed and receives the echo after 0.160 s. The speed of sound in sea water is 1500 m/s. Calculate the depth of the water. (3 marks)Question 4 Two sounds (4 marks)
- State which trace shows the sound with the higher pitch. (1 mark)
- State which trace shows the louder sound. (1 mark)
- Calculate the frequency of the sound in trace X. (1 mark)
- Calculate the wavelength of X in air, using 330 m/s. (1 mark)
Question 5 Sound in air (3 marks)
Describe how a sound wave travels through air from a loudspeaker to a listener. (3 marks)Question 6 Sound and vacuum (2 marks)
Explain why sound cannot travel through a vacuum. (2 marks)Question 7 Medical ultrasound (2 marks)
Explain how an ultrasound scan produces an image of an organ. (2 marks)Question 8 Speed in air (1 mark)
State the speed of sound in air used in this course. (1 mark)
