Question

Calculate the amount of work to stop a car of 1000kg moving with a speed of 72km/h.

Answer 1

Here ,

Initial Velocity = u = 72 km/h = 20m/s

Final Velocity = v = 0 m/s

Mass of the body = m = 1000 kg

Now using the concept of Work Energy Theorem :

Work Done = ½mv²-½mu² = 0-½×1000×20 = 10000 N

The total work done is 10000 N.