Question

Explain this numerical.​

Answer 1

Explanation:

A car was initially in motion. Its velocity was u. Then it produced acceleration opposite to direction of initial motion. Magnitude of acceleration ā is 6m/s². To stop the car, it takes 2s after brakes are applied. Now final velocity(v) is 0. It is asked to find Displacement.

We know ā=(v-u)/t but v is 0 so ā=-u/t ( we avoid - sign because we are squaring "-u" further. )

-ut=ā but we will say ā=ut

Now use u=at to find u which will be 12 m/s.

Now use v²=u² + 2āS

0²= (-12)² +( 2×6×S)

0= 144 + 12S

-12S= 144

-S= 144/12

S=-12 m

-12 m means 12 m opposite to direction of Motion.