5) A person holds a 1.7 kg bucket and lets it move down at constant speed 75 cm to the floor.
What is the work done on the bucket by the person?

12.5J

Explanation:

Given parameters:

Mass of bucket  = 1.7kg

Height  = 75cm  = 0.75m

Unknown;

Work done on the bucket by the person  = ?

Solution:

To solve this problem, we use the work done equation;

  Work done  = force x distance  = mgh

 m is the mass  

  g is the acceleration due to gravity

  h is the height

Now, insert parameters and solve ;

     Work done  = 1.7 x 9.8 x 0.75  = 12.5J