m schemes(work, energy and power)

AS and A Level Physics Original material © Cambridge University Press 2010 1

5 Marking scheme: Worksheet (AS)

1 C [1]

2 D [1]

3 C [1]

4 A [1]

5 D [1]

6 Meteor: J 103.15000010.02

1

2

1 522k mvE [1]

Jogger: J 8100.5652

1

2

1 22k mvE [1]

The meteor has greater kinetic energy than the jogger. [1]

7 a Ep mgh

Ep 9.0 9.81 3.5 [1]

J 310J 309pE [1]

b t

WP

60

309P [1]

W2.5P [1]

8 a Using the principle of conservation of energy:

final kinetic energy loss of gravitational potential energy

final kinetic energy mgh 0.800 9.81 5.0 [1]

final kinetic energy J 39J 2.39 [1]

b Maximum gravitational energy after bounce 0.800 9.81 3.8 29.8 J [1]

Kinetic energy just after rebound 29.8 J

8.29800.02

1 2v [1]

1s m 6.8800.0

8.292v [1]

c Energy transfer to ground 39.2 29.8 = 9.4 J [1]

9 a Ep mgh

Ep 35 9.81 (1.5 0.80) [1]

J 240pE [1]

b mghmv2

2

1

v2 2gh 2 9.81 (1.5 0.80) [1]

1s m 7.3v [1]

c There is no distance moved in the direction of the tension in the rope, since the motion is

always at right angles to the rope. Hence, no work is done by the tension. [1]

5 Marking scheme: Worksheet (AS)

AS and A Level Physics Original material © Cambridge University Press 2010 2