Question

A 10-kg dog is running with a speed of 5.0 m/s. what is the minimum work required to stop the dog in 2.40 s?

Answer 1

Answer;

Work = 125 joules

Explanation and solution;

• Work is the product of force and the distance covered. Therefore, Work = force × distance.

• Work is measured in joules.
• Work is also a change in energy, such that work is done when energy changes, so when kinetic energy, or potential energy changes the there is work being done.

Thus; kinetic energy = work done

Kinetic energy = 1/2mv²

                       = 1/2 × 10× 5²

                       = 5 × 25

                       = 125 joules

Hence, work done is 125 joules.