An engineer uses an electric pump to lift a fixed volume of water up to a storage tank at a height of 5.0 m. She then increases the electrical input power to the pump and repeats the process with the same volume of water. The efficiency of the pump remains constant.
Which row in the table correctly describes the effect of this increase on the useful work done in lifting the water and the time taken to fill the tank?
| Useful work done | Time taken | |
|---|---|---|
| A | decreases | decreases |
| B | stays the same | decreases |
| C | stays the same | increases |
| D | increases | stays the same |
Row A
Row B
Row C
Row D
533 exam-style questions on CIE IGCSE Physics 1.7 Energy, work and power, covering 1.7.1a Energy stores and energy transfers, 1.7.1b Conservation of energy, 1.7.1c Kinetic and gravitational potential energy, 1.7.2 Work done, 1.7.3 Energy resources, 1.7.3a Energy resources and electricity generation, 1.7.3b Nuclear fusion as an energy source, 1.7.3c Efficiency of energy transfer, and 1.7.4 Power. Each one has a worked solution and a mark scheme showing where the marks go.