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GCSE Questions - Waves

Q8. Starter pistols are used in athletics events to start races. A starter pistol makes a loud bang and produces a puff of smoke.

The diagram shows Buffy and Willow investigating the speed of sound using a starter pistol and a stopclock.

(a) Willow sees the puff of smoke before hearing the bang from the starter pistol. What does this tell you about the speed of sound compared with the speed of light?

Light travels faster than sound.

[1 mark]

(b) The frequency of the sound wave produced by the pistol was 800 Hz The wavelength of the sound wave was 42 cm Calculate the speed of the sound wave.

wavespeed = frequency x wavelength

wavelength has to be in metres: λ = 42 cm = 0.42m

wavespeed = 800 x 0.42

wavespeed = 336 m/s

[4 marks]

(c) Complete the table below to show the properties of the sound wave at Point B compared with the sound wave at Point A.

Tick one box for each property comparison.

Properties of the sound wave at Point B compared to Point A
greater than
less than
the same as
amplitude
  
frequency
  
speed
  

[3 marks]

(d) A sound wave can be reflected. What name is given to a reflected sound wave? Echo

[1 mark]

(e) Which two of these statements are true for sound waves?

 
Tick here
Sound waves can travel through a vacuum.  
Sound waves are transverse waves.  
Sound waves are longitudinal waves.
Sound waves transfer energy.
Sound waves are electromagnetic waves.  

[2 marks]

(Total 11 marks)