A student climbs a staircase from the ground floor to the first floor landing above…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A 60kg student climbs a staircase from the ground floor to the first floor landing 4.5m above and then continues to the second floor landing 9.0m above the ground. The time taken for each part of the climb is 20s. Take g=9.8m/s2.
(i) Derive an expression for the change in gravitational potential energy when the student ascends from one floor to another of height h.
(ii) Calculate the change in gravitational potential energy for the first climb (ground to first floor).
(iii) Calculate the change in gravitational potential energy for the second climb (first floor to second floor).
(iv) Determine the average power developed by the student during each part of the ascent.
(v) Compare the two power values and explain any difference observed.