Work Done Against the Force of Gravity
Example:
Ranjit runs up a staircase of 35 steps. Each step is 15cm in height. Given that Ranjit’s mass is 45kg, find the work done by Ranjit to reach the top of the staircase.
Answer:
In this case, Ranjit does work to overcome the gravity.
Ranjit’s mass = 45kg
Vertical height of the motion, h = 35 × 0.15
Gravitational field strength, g = 10 ms-2
Work done, W = ?
W = mgh
W = (45)(10)(35 × 0.15)
W = 2362.5J