Page 53 - SP015 Past Years PSPM Chapter 1 -5 Ver.2020

PSPM SP015

Power

UPS 2011/2012 SF016 No. 4(a)(i)

32. Define power. [1 m]

PSPM JAN 1999/2000 SF015/2 No. 4

33. metal plate

marble
spring

FIGURE 5.17
-1
A 0.2 kg marble moves at constant velocity 10.0 m s before it hits the metal plate that
is stuck on a spring as shown in FIGURE 5.17.

(a) If initially the marble has power of 10 W, what is the force acting on the marble?
[2 m]
(b) If the spring is compressed 10.0 cm, determine the elastic spring constant. [2 m]

PSPM JAN 1999/2000 SF015/2 No. 11(b)

-1
34. (a) A car of mass 1500 kg moves on a horizontal road at constant velocity 30 m s .
Coefficient of kinetic friction between the tyres and the surface of the road is 0.04,
determine the power produced by the engine. [2 m]

(b) The same car then climbs up a hill inclined at an angle 6 with the same friction
between the tyres and the surface of the road is 0.04. With an aid of a diagram,
show all the forces acting on the car and determine the power required by the car
to move with the same velocity. [6 m]

PSPM 2004/2005 SF017/2 No. 2

35. A Proton car has maximum power of 82 kW and may attain maximum speed of
-1
190 km h . Calculate the force of the car at maximum speed. [4 m]

UPS 2005/2006 SF017 No. 4

3
-1
36. A car of mass 2.1  10 kg travelled with an initial speed of 15.0 m s . If it accelerates
-2
at a rate of 2.5 m s for 10 s, calculate
(a) the change in kinetic energy. [2 m]
(b) the power of the car. [2 m]

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