A porter moves a suitcase between two points within the same building
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A porter moves a suitcase between two points within the same building.
The initial point A is on the ground floor and the final point B is on the first floor, situated vertically 4.0 m above A. The porter may choose any route inside the building – for example, a straight lift ride, or a long sloping ramp that spirals upward.
Answer the following:
(i) What is meant by the work done by a force between two specified points?
(ii) The porter first walks horizontally 12 m, then climbs the ramp rising uniformly through 4.0 m along a 25 m path. Would the work done by the gravitational force during this motion depend on the horizontal segment? Give reasons.
(iii) A friend claims that taking the lift (which rises vertically 4.0 m) makes the gravitational force perform less work than walking up the ramp. Evaluate this claim with proper justification.