How much work must be done by frictional forces in slowing a 1000-kg car from 26.1 m/s to rest?

Work done by the frictional force is 3.41x10^5 J

It is given that,

Mass of the car, m = 1000 kg

Initial velocity of car, u = 26.1 m/s

Finally, it comes to rest, v = 0

We have to find the work done by the frictional forces. Work done is equal to the change in kinetic energy as per work - energy theorem i. e.

W = - 340605 J

or Hence, the correct option is (a).