Physics: Energy resources and energy transfer

What is the principle of the conservation of energy?

• Energy can never be created or destroyed; it can only be converted from one form to another.

• Energy can be created or destroyed; it can also be converted from one form to another.

A light bulb has a total energy input of 200J. 190J of this is wasted energy. Work out the energy efficiency.

• 10%

• 5%

• 90%

Draw a Sankey diagram for a candle which wastes most of its energy as heat.

Which type of heat energy transfer only takes place in fluids and involves warmer, less dense regions of fluid moving upwards and being replaced by colder, sinking fluids?

• Conduction

• Convection

• Radiation

Which of these loses energy more quickly?

• A bright, shiny surface

• A dull, black surface

Find the work done by a car driving at a force of 500N 200m down a road.

• 1000J

• 5000J

• 700J

• 300J

How fast does a stone weighing 4kg fall from a height of 200m?

• 28 m/s

• 800 m/s

• 63 m/s