A toolbox is lifted from the floor to the top of a workbench that is high
PHYSICS · Multi-part · CBSE · Physics · Work and Energy · Work and Energy
Problem
A 1.2kg toolbox is lifted from the floor to the top of a workbench that is 0.95m high. Assume that air resistance is negligible and that the toolbox moves only in the vertical direction.
(1) Taking the floor as the reference position where gravitational potential energy is zero, calculate (i) the gravitational potential energy of the toolbox at the top of the bench and (ii) the change in gravitational potential energy during the lift.
(2) Taking instead the workbench surface as the reference position where gravitational potential energy is zero, calculate (i) the gravitational potential energy of the toolbox at the floor level and (ii) the change in gravitational potential energy during the lift.
(3) Using the work–energy theorem, determine the amount of work done on the toolbox by the lifting force in either reference choice and explain why the numerical value is the same.