Question

A car of mass 1000 kg moving with velocity 54 km/h stops in 5 seconds. Calculate the force applied by brakes.
Give the solution with the answer.

Answer 1

here is ur answer u have to convert the unit of velocity into m/ sec
if any doubt plz ask..

Answer 2

Given is the mass of the car to be 1000kg along with the velocity of 54km/h. first of all, the velocity is to be changed into SI unit i.e. m/s. and then from the given time of 5 seconds, the acceleration is to be calculated.

The calculated acceleration will then be put into the formula of force calculation to calculate the force with which the brakes were applied.

$V=54\frac { km }{ h } =54\times \frac { 5 }{ 18 } =15\frac { m }{ s }$. t = 5 sec.

$\Rightarrow a=\frac { v }{ t } =\frac { 15 }{ 5 } =3\frac { m }{ { s }^{ 2 } }$.

$Force = mass\times acceleration$

$\Rightarrow F = 1000\times 3 = 3000 N$.