A motor pulls a communications cable through three straight sections of an underground duct. The pulling force acts along the direction in which the cable moves.
The cable rubs against the inside of the duct and moves at a constant speed.
| Section | Pulling force / N | Distance moved / m |
|---|---|---|
| A | 45 | 60 |
| B | 75 | 40 |
| C | 120 | 55 |
Calculate the total work done by the motor while the cable moves through sections A and B.
The motor can do a maximum of 12.0 kJ of work before its energy supply is exhausted.
Use the table and your answer to part (a) to determine whether the motor can pull the cable through all three sections.
Explain why the kinetic energy store of the cable remains unchanged even though the motor does work on the cable.
113 exam-style questions on AQA GCSE Physics 5.2 Work done and energy transfer, covering 5.2 Work done and energy transfer. Each one has a worked solution and a mark scheme showing where the marks go.