A family compares two vacuum cleaners, X and Y.
The Table shows information about the vacuum cleaners.
Table
| Vacuum cleaner | Total power input in W\text{W}W | Useful power output in W\text{W}W |
|---|---|---|
| X | 1600 | 480 |
| Y | 900 | 360 |
Calculate the efficiency of vacuum cleaner X.
Calculate the efficiency of vacuum cleaner Y and state which vacuum cleaner is more efficient.
Vacuum cleaner Y is used for 15 minutes.
Calculate the total energy supplied to vacuum cleaner Y.
A salesperson says:
'Vacuum cleaner X is better because it has a greater power input.'
Explain why vacuum cleaner X wastes more energy each second than vacuum cleaner Y.
128 exam-style questions on Edexcel GCSE Physics 8.3 Power and efficiency, covering 8.3.1 Power and 8.3.2 Efficiency. Each one has a worked solution and a mark scheme showing where the marks go.