What is the minimum work that a motor must do to lift a 70 lb object from the floor to a height of 14 feet?
A) 5
B) 70
C) 700
D) 980
E) 2010 ft-lbs

Question

Quizplus · Accepted Answer

The formula for work is Work = Force x Distance. 
In this case, the force needed to lift the object is its weight, which is 70 lbs. 
The distance it needs to be lifted is 14 feet.

Therefore, the work required is: 
Work = 70 lbs x 14 feet 
Work = 980 ft-lbs

Thus, the minimum work the motor must do is 980 ft-lbs, which is option D.

What Is the Minimum Work That a Motor Must Do