Distance after breaking work ?

1 Answer
Mar 5, 2017

Both cover the same distance.

Explanation:

Let p=m1v1=m2v2 be the momentum attached to car and lorry.

The work needed to attain rest is in each case

The momentum mv has associated a mechanical energy given by 12mv2. Also f is the resistive force the same for both cars and w is the dissipated mechanical energy, as breaking work.

12m1v21=w1=fd1 and
12m2v22=w1=fd2

Here d1,d2 are the distances covered until rest. Dividing term to term

m1v21m2v22=d1d2

but m1v1=m2v2 so d1d2=1 hence d1=d2