Page 48 - SP015 Past Years PSPM Chapter 1 -5 Ver.2020

PHYSICS PSPM SEM 1 1999 - 2017

UPS 2006/2007 SF017 No. 4(b)

18. A 60 g object is dropped from a height of 2.0 m. After striking the floor, the object
rebounds vertically upwards, losing 25% of its initial energy. During its first rebound,
calculate
(a) the initial velocity of the object. [5 m]
(b) the maximum height of the object. [3 m]

(Ignore air resistance)

UPS 2008/2009 SF017 No. 4

19.
Circular 20 mm
track 0.1 m

FIGURE 5.8

A 0.002 kg ball bearing is placed at one end of a spring and the spring is compressed by
20 mm as shown in FIGURE 5.8. A 0.4 N force will compress it 1.5 mm

(a) Calculate the energy stored in the spring. [3 m]
(b) Based on the work-energy theorem, why does the ball maintain a constant
horizontal velocity after being released? [4 m]
(c) If the ball then travels up a vertical frictionless circular track of radius 0.1 m,
calculate the speed of the ball at the highest point of the track. [3 m]

UPS 2009/2010 SF017 No. 4(b)

20.

 50

A

FIGURE 5.9

A pendulum with a string of length  = 2.2 m is released from point A as shown in as
shown in FIGURE 5.9. Determine the speed of the pendulum when it reaches the
lowest point. [4 m]

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