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Sketch two cycles of the displacement-time (x-t) relationship for a simple pendulum. Assume that its
displacement is a maximum at time 0 seconds. Mark on the graph a time for which the velocity is maximum
(labeled A), a time for which the velocity is zero (labeled B) and a time fro which the acceleration is a
maximum (labeled C).
Calculate the phase difference between the two displacement-time graphs shown in the figure. Give
your answers in
a) seconds ...............................; b) radians ...............................; c) degrees ..............................................
Question 13-14, Waves on a string:
A travelling wave is created on a string. The graph below shows the variation with time t of the displacement y of a particular point on the string.
The variation with distance x of the displacement y of the string at t = 0 is shown below.
Use information from the graphs to calculate, for this wave,
(i) the wavelength;
(ii) the frequency;
(iii) the speed of the wave;
Show that the intensity at 120 m from the source is approximately 3.0 × 10^−6 𝑊 ∙ 𝑚−2.
If the distance is kept constant, the amplitude is changed to make the intensity to 3.0 ×
10−6𝑊 ∙ 𝑚−2. Deduce how the amplitude of the wave changes.
Question 16-17 are about waves.
In the scale diagram below, plane wavefronts travel from medium 1 to medium 2 across the boundary AB.
State and explain in which medium the wavefronts have the greater speed.
By taking measurements from the diagram, determine the ratio
