Page 37 - SP015 Past Years PSPM Chapter 6 -14 Ver 2020

PSPM SP015

PSPM 2012/2013 SF016/2 No. 6(b)

26. y (cm)

5

0 2 4 6 t (s)

–5

FIGURE 9.8

FIGURE 9.8 shows a displacement-time graph of simple harmonic motion. Determine

(a) the amplitude. [1 m]

(b) the frequency. [2 m]
(c) the angular frequency. [2 m]

(d) the equation for the simple harmonic motion. [2 m]

PSPM 2014/2015 SF016/2 No. 6(b)

27. A 25 g block connected to one end of a spring is displaced 15 cm from its equilibrim
-1
position and released. The spring constant is 180 N m .

(a) Write the acceleration a of simple harmonic motion equation of the block in terms
of displacement x. [1 m]

(b) Sketch the graph of displacement versus time of the block. Label the amplitude
and the period of oscillation on the graph. [2 m]

(c) Calculate the instantaneous speed of the block at a distance 11 cm from the
equilibrium position. [3 m]

(d) Calculate the total energy of the system. [2 m]

(e) On the same graph, sketch and label the variation of kinetic energy K and
potential U versus displacement x. On the graph, indicate the maximum value of
each curve (if any) and the amplitude. [3 m]

(f) The spring is removed and then 25 g block is connected to the a string. The string-
block system oscillates as a simple pendulum. What effect on the period of
oscillation if the mass of the block is reduced by half? Explain your answer.
[2 m]

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