Question

A 1200kg car is traveling at 25m/s. How much kinetic energy does the car have? What amount of work would be required to bring the car to a stop?

Answer 1

KE = 1/2mv^2
= (0.5)(1200)(25)^2
= 375,000 J

Answer 2

Assuming that the car is travelling in a horizontal plane on a frictionless surface, the work-kinetic energy theorem shows that it would take 375,000 J of work to bring the car to a stop.

Answer 3

@ospreytriple How would I show work for that

Answer 4

It said W = KEf - KEi

Answer 5

It said W = KEf - KEi

Answer 6

Try this;
\[W=\Delta E_k\]\[=E_{k,f} - E_{k,i}\]\[=0-375,000 \text{ J}\]\[=-375,000 \text{ J}\] and since energy is being removed from the object, work is negative.