A car accelerates uniformly from $18 km/h$ to $36 km/h$ in $5\ second$. Calculate the acceleration.

Here given, the initial velocity of the car $u=18\ km/h=18\times\frac{5}{18}=5\ m/s$

The final velocity of the car $v=36\ km/h=36\times\frac{5}{18}\ m/s=10\ m/s$

Time $t=5\ second$

Therefore, acceleration $a=\frac{v-u}{t}$

$=\frac{10-5}{5}$

$=\frac{5}{5}$

$=1\ m/s^2$

Therefore, the acceleration of the car is $1\ m/s^2$.