GCSE Questions - Waves

Q14. Here is some apparatus that can be used to investigate the waves in a stretched string.The frequency of the signal generator is adjusted so that a wave is seen - as shown in the diagram. At this frequency the string vibrates between the two positions shown in the diagram.

(a) The wavelength of the wave shown in the diagram was measured as 80 cm. What piece of apparatus would have been suitable for measuring this wavelength?

[1 mark]

(b) Write down the equation which links frequency, wavelength and wave speed.

[1 mark]

(c) The string vibrates at 55 Hz. Calculate the wave speed of the wave. Use the data given in the diagram.

[3 marks]

(d) The frequency of the signal generator is increased. This makes the wavelength of the wave change. The wave speed stays the same.

Describe how the apparatus could be adjusted to show one complete wave without reducing the frequency.

[2 marks]

(e) A student wants to investigate how the speed of a wave on a stretched string depends on the tension in the string. The student uses the apparatus in the diagram above.

Describe a method the student could use for this investigation.

[4 marks]

(Total 11 marks)