A worker pushes a crate of mass 40 kg up a ramp at a constant speed.
The ramp is 5.0 m long and rises through a vertical height of 1.2 m.
The worker pushes with a constant force of 150 N parallel to the ramp.
The gravitational field strength is 10 N/kg.
Calculate the work done by the worker in pushing the crate to the top of the ramp.
Calculate the gravitational potential energy gained by the crate.
Calculate the average frictional force on the crate as it moves up the ramp.
The worker says:
'The energy that did not go into the gravitational potential energy store of the crate has been used up.'
Evaluate this statement.
44 exam-style questions on OCR GCSE Physics 7.1 Work done, covering 7.1.1 Conservation of energy in a closed system, 7.1.2 Energy stores and transfers, 7.1.3 Energy changes by heating, forces and current, 7.1.4 Quantifying energy transfers in a system, and 7.1.5 Kinetic, elastic and gravitational potential energy. Each one has a worked solution and a mark scheme showing where the marks go.