GSO001 Problem 3
Problem Statement
Work and Power Required to Lift a Load
Problem Statement
In a space where gravitational acceleration g acts downward, an object of mass m is lifted from the ground to height h at a constant speed. Find the work W done by the lifting force on the object. Then find the power P when this lifting operation takes time t.
Constraints
- Mass m=25 kg
- Gravitational acceleration g=9.8 m/s2
- Height h=12 m
- Time t=14 s
Input Format
Find the value of power P and give the answer as a positive integer.
Solution
This problem consists of two steps: the definition of work and the definition of power.
1. Step 1: Computing Work W
The force F required to lift the object at constant speed equals gravity mg. The work W done in moving the object to height h is:
W=F×h=mghSubstituting numerical values:
W=25 kg×9.8 m/s2×12 m=2940 J2. Step 2: Computing Power P
Power P is the amount of work done per unit time, found by dividing work W by the elapsed time t:
P=tWSubstituting W and t:
P=14 s2940 J=210 WTherefore, the power is 210.
Answer: 210