Question

A car of 1000 kg with velocity 18 km/hr is stopped by brake of 1000 N. distance covered by it before stopping is

Answer 1

f=ma

1000=1000*a

a=-1m/s^2(retarding)

v=0

u=18km/h=5m/s

v^=u^2=2as

0=25+2*-1*s

-25/-1=s

s=12.5m