Question

A car moving with an initial velocity of $60m/s$ is brought to rest in $30s$. Calculate the acceleration?

Answer 1

Step 1: Given:

Initial velocity, $u=60m/s$,

Final velocity, $v=0m/s$,

Time, $t=30s$

Step 2: Formula used: Using the first equation of motion.

$$\begin{gathered} v=u+at \\ Where,visfinalvelocity,uisintialvelocity,aisaccelerationandtistime \end{gathered}$$

Step 3: Final solution;

$$\begin{gathered} v=u+at \\ 0=60+a\times 30 \\ a=-2m/s^2 \end{gathered}$$

Hence the acceleration of the car is $-2m/s^2$.