During a certain time interval, a 20-n object free-falls 10 meters. the object gains joules of kinetic energy during this interval

200 J

Explanation:

By the law of conservation of energy, the kinetic energy gained by the object during the fall is equal to the loss of gravitational potential energy:

The loss of gravitational potential energy of the object over a distance of 10 m is given by:

where

(mg) = 20 N is the weight of the object

h = 10 m is the loss in height

Substituting, we find

So, the kinetic energy gained by the object is