Page 19 - SP015 Past Years PSPM Chapter 6 -14 Ver 2020

PSPM SP015

PSPM 2013/2014 SF016/2 No. 5(b)

20. A ceiling fan is rotating at an angular speed of 300 rpm when the switch is turned off. It
takes 45 s for the fan to stop. Calculate the

(a) average angular acceleration. [2 m]

(b) number of revolution the fan makes before it stops. [2 m]

PSPM 2014/2015 SF016/2 No. 5(a)(ii)

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21. At the instant a ceiling fan is switched off, the angular velocity of the fan is 65 rad s
and stop after 9 s. Calculate the number of rotation for the fan to stop completely.
[2 m]

PSPM 2017/2018 SF016/2 No. 5(b)

22. A disc of 8.0 cm in radius rotates at a constant rate of 1200 revolution per minute about
its central axis. Calculate the

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(a) angular velocity in rad s . [2 m]

(b) tangential speed at a point 3.0 cm from its centre. [2 m]

(c) Distance travelled by a point at the edge of the disc in 2.0 s. [2 m]

Rotational Dynamics

PSPM 2013/2014 SF016/2 No. 5(a)(ii)

23. Define moment of inertia. [1 m]

PSPM 2011/2012 SF016/2 No. 5(a)

24. State three (3) factors which affect the moment of inertia of a rigid body. [2 m]

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