Describing waves
3 marks · NormalA student is investigating waves along a stretched rope. She creates 12 complete waves in 3 seconds.
Calculate the frequency of the waves.
State the unit for frequency.
Explain what is meant by the ‘frequency’ of a wave.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) 4 Hz
(b) hertz (Hz)
(c) The number of waves produced or passing a point per second.
Common mistakes: Incorrect calculation of frequency (not dividing by time); Incorrect unit for frequency
Show mark scheme and worked solution
Marking points
M1 (a) · 1 mark · Correct calculation: frequency = number of waves ÷ time (12 ÷ 3)
B1 (b) · 1 mark · Correct unit for frequency: hertz/Hz
B1 (c) · 1 mark · Accurate description of frequency.
Worked solution
a) Frequency = Number of waves / Time = 12 / 3 = 4 Hz
b) The unit for frequency is hertz (Hz).
c) Frequency is the number of waves produced or passing a point per second.