- #1
hamza2095
- 28
- 1
Homework Statement
A mass of 235kg is lifted by a winch and an electric motor. The motor does 1800J of work on the mass to raise it to an upper floor. The electric energy needed to complete this task is 160,000J
Homework Equations
I know the solution but I don't why it is the solution
Solution:
m*g*h = W
h = 1800J/(235kg*9.5N/Kg)
= 0.78m
The Attempt at a Solution
I think it's because the mechanical energy (Em= Ek + Eg) is 1800J and when the mass is at the top all the energy is in the form of gravitational potential energy because the velocity is 0, making the kinetic energy 0.
I want to know why so if on a test there is a similar question I know how to do it