Exam code: YPH11
A crane lifts a container of weight 4.0 × 105 N through a height of 25m.
Which of the following gives the gravitational potential energy gained by the container in joules?
4.0 × 105 × 9.81 × 25
4.0 × 105 × 25
4.0 × 105 × 25 ÷ 9.81
4.0 × 105 ÷ 9.81
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The diagram shows the momentum of two trolleys, X and Y, before a collision. The mass of each trolley is 0.25 kg.
The two trolleys join together after the collision and move on with a velocity of 1 m s−1 .
Which of the following is the kinetic energy of trolley X before the collision?
0.5 J
1 J
2 J
4 J
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A hydroelectric power station has an efficiency of 32%. In one hour the useful energy output of the power station is 1.2 × 1013 J.
Which of the following expressions gives the total power input to the power station in watts?
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A tractor pulls a trailer a distance s in time t. The useful power output of the tractor is P.
Which of the following equations gives the force F of the tractor on the trailer?
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An electric motor lifts a load of weight through a vertical height of in . The motor is connected to a supply and draws a current of .
Which of the following expressions gives the efficiency of the motor, as a percentage?
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