A crane lifts a crate at a steady speed.
The weight of the crate is 6000 N. The crane lifts the crate through a height of 15 m. This takes 1.5 minutes.
State what is meant by power.
Use the equation: work done=force×distance\text{work done} = \text{force} \times \text{distance}work done=force×distance
Calculate the work done on the crate by the crane.
Use the equation: power=work donetime\text{power} = \dfrac{\text{work done}}{\text{time}}power=timework done
Calculate the power of the crane.
A second crane lifts an identical crate through the same height in 1.0 minute.
Explain why the second crane has a greater power.
50 exam-style questions on OCR GCSE Physics 2.2 Newton’s laws, covering 2.2.1 Interactions between objects, 2.2.2 Force pairs in interactions, 2.2.3 Forces as vectors, 2.2.4 Newton's first law, 2.2.5 Resolving forces with vector diagrams, 2.2.6 Forces acting on an isolated object, 2.2.7 Free body diagrams and resultant force, 2.2.8 Free body diagrams for balanced forces, 2.2.9 Newton's second law, 2.2.10 Inertia and inertial mass, 2.2.11 Momentum in collisions, 2.2.12 Relating force, mass, velocity and acceleration, 2.2.13 Work done by a force, 2.2.14 Work, stored energy and units of energy, 2.2.15 Power as the rate of energy transfer, 2.2.16 Newton's third law, and 2.2.17 Circular motion and changing velocity. Each one has a worked solution and a mark scheme showing where the marks go.