A radio-wave source emits a pulse towards a reflector. After bouncing back, the pulse is detected at the same location as the source. The outgoing and returned pulses are displayed on a cathode-ray oscilloscope (c.r.o.) as shown in Fig. 2.1. The time-base setting is $0.20\,\mu\text{s cm}^{-1}$.
(a)[4]
Using Fig. 2.1, determine how far the reflector is from the source.
(b)[3]
Determine the time-base setting needed to give the same pulse separation on the c.r.o. when sound waves replace radio waves. The speed of sound is $300\,\text{m s}^{-1}$.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “$d = v \times t$” …