Describing waves
2 marks · EasyA water wave has a wavelength of 0.8 m. It completes 6 waves every second.
(a)[1 mark]
State the frequency of the wave.
(b)[1 mark]
How many wavelengths pass a fixed point in 2 seconds?
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Show answer
(a) 6 Hz
(b) 12 wavelengths
Common mistakes: Dividing instead of multiplying in part b
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · States frequency as 6 Hz (one mark).
B1 (b) · 1 mark · Correctly calculates 12 wavelengths in 2 seconds.
Worked solution
a) Frequency = number of waves per second = 6 Hz.
b) In 2 seconds: 6 waves/sec × 2 sec = 12 wavelengths pass the point.