A kettle is found to output 65J when its input energy is 100J. What is the efficiency of the kettle, and what happens to the rest of the energy?

Efficiency=useful energy /input energy x 100, so for the kettle, efficiency = 65/100 x 100 = 65% efficient. The rest of the energy is wasted as heat energy in the kettle/sound energy.

JL

Related Physics GCSE answers

All answers ▸

Explain the difference between energy and power.


Why do objects reach terminal velocity?


What name is given to the phenomena which results in longer wavelengths of light being observed from distant galaxies and why does this occur?


When the current through an ohmic conductor is 2A, the potential difference across it is 6V. What is the potential difference across the same ohmic conductor when the current is increased to 3A?