Page 202 - Physics Coursebook 2015 (A level)

Cambridge International AS Level Physics
5 The diagram represents a wave on the surface of water at one instant of time. The speed of the wave is 7.0 cm s–1. Calculate the amplitude, wavelength and time period for one oscillation.
6 a
Light is referred to as a type of electromagnetic wave. Explain what is meant by the term
20 mm
9.0 cm
Figure 13.19 For End-of-chapter Question 5.
12 mm
electromagnetic wave. [2]
b i Two stars emit radiation with the same power. Star A is twice as far from the Earth as star B.
Explain how the intensities of the radiations compare to an observer on the Earth. [2] ii State how the amplitudes of the two signals received by the observer compare. [2]
c The main signal from star A is in the ultraviolet region of the spectrum with a wavelength
of 7.5 × 108 m. Calculate the wavelength of this radiation. [2]
7 Figure 13.20 shows a loudspeaker producing a sound and a microphone connected to a cathode-ray oscilloscope.
loudspeaker microphone
Figure 13.20 For End-of-chapter Question 7.
a Sound is described as a longitudinal wave. Explain how the trace on the oscilloscope relates
to the movements of the air particles in the sound wave. [3]
b The time-base on the oscilloscope is set at 5 ms div−1. Calculate the frequency of the wave. [2]
c The wavelength of the wave is found to be 1.98 m. Calculate the speed of the wave. [2]
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