Page 7 - SP015 Past Years PSPM Chapter 6 -14 Ver 2020

PSPM SP015

PSPM 2014/2015 SF016/2 No. 3(c)

21.
7 m

8 m

FIGURE 6.9

A theme park ‘loop the loop’ ride has a loop of radius 8 m. A 90 kg car goes around the
inside of the loop after descending from vertical height of 7 m above the top of the loop
as in FIGURE 6.9. Calculate

(a) the centripetal acceleration of the car, [3 m]
(b) the force exerted on the car [3 m]

when it is on the top of the loop.

PSPM 2014/2015 SF016/2 No. 4(a)

22. Two ice skaters, each of mass 60 kg hold hands and spin in a circle with a period of
4.3 s. The distance between them is 1.44 m.

(a) Calculate the angular velocity. [1 m]
(b) Calculate the centripetal acceleration. [1 m]
(c) Calculate the pulling force that acts on each hand. [1 m]

(d) Describe their subsequent motion after they separate. [1 m]

PSPM 2015/2016 SF016/2 No. 4(a)(ii), (iii)

23. (a) A cyclist rides on a horizontal circular track. With the aid of an appropriate
labeled force diagram, explain why the cyclist has to lean towards the centre of
the track. [2 m]

(b) Refer to the cyclist in question (a). Let v be the maximum speed of the cyclist, r

the radius of the track,  the coefficient of friction between the tyres and track,
and g the gravitational acceleration. Determine  in terms of v, r and g. [5 m]

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