IGCSE work power thermal test

Which energy source is one that is used to boil water to make steam in power stations?

• energy from tides

• energy from waves

• hydroelectric energy

• nuclear energy

Two workers are stacking cans on to a shelf in a shop. The workers lift the same number of

identical cans on to the same shelf from the same level.

Worker P takes 3.0 minutes to lift the cans. Worker Q takes 4.0 minutes to lift the cans.

Which statement about the workers is correct?

• Worker P develops less useful power than worker Q.

• Worker P develops more useful power than worker Q.

• Worker P does less useful work than worker Q.

• Worker P does more useful work than worker Q.

A ball is dropped on to a hard surface and bounces. It does not bounce all the way back to where

it started, and so has not regained all of its original gravitational potential energy.

Which statement accounts for the loss of gravitational potential energy?

• Energy was destroyed as the ball hit the ground.

• Energy was destroyed as the ball travelled through the air.

• The chemical energy and elastic energy of the ball have increased.

• The internal (heat) energy of the ball and its surroundings has increased.

To calculate the power produced by a force, the size of the force must be known.

What else needs to be known to calculate the power?

• A

• B

• C

• D

Four different model steam engines each lift a 1.0kg object from the same laboratory floor to the

same laboratory bench. Each engine takes a different time to lift the object.

How does the most powerful engine compare with the other engines?

• A

• B

• C

• D

Electrical energy may be obtained from nuclear fission.

In which order is the energy transferred in this process?

• nuclear fuel → generator → reactor and boiler → turbines

• nuclear fuel → generator → turbines → reactor and boiler

• nuclear fuel → reactor and boiler → generator → turbines

• nuclear fuel → reactor and boiler → turbines → generator

A certain machine is very efficient.

What does this mean?

• It produces a large amount of power.

• It uses very little energy.

• It wastes very little energy.

• It works very quickly.

A car moves along a level road at constant speed. Work is done by the engine and power is

developed by the engine.

Which pair of graphs shows how the work done and the power developed vary with time?

• 
• 
• 
• 

A force F moves a load from the bottom of a slope to the top.

The work done by the force depends on the size of the force, and on a distance.

What is this distance?

• p

• q

• r

• p + q

Which energy resource does not derive its energy from the Sun?

• geothermal

• hydroelectric

• oil

• waves