Question

the brakes applied to a car produce an acceleration of 6 metre per second square in the opposite direction to the motion if the cars take 2 second to stop after the application of brakes calculate the distance it travels during the time

Answer 1

hey mate!! here is your answer
given,
v=0
a=-6ms^-2
t=2secs
u=??

by the equation v=u+at we find initial velocity of the car because it's not given then by the equation 2as=v^2-u^2 we can get the distance travelled in that time.
so, by the first equation we have
u=v-at that is u equals 0-12=12m per sec (ignoring the negative sign)
now to find the distance travelled =2×-6=0^2 - 12^2
=>-12s=-144
=>s=-144/-12=12metres
therefore the distance travelled is 12metres.