A classical mechanics problem by Tan T

We use the formula $v = u + at$ here. Where $v$ is the final velocity, $u$ initial velocity, $a$ is the acceleration and $t$ is the time taken.

After applying brakes the car comes to rest, so the final velocity is zero.

$u + at = 0$

Here, $u = 36km/h = 10m/s$ , $a = \frac{5}{6} m/s^2$

And total time was 14 seconds. And we don't know the time taken for the car to stop.

So From the above equation we get, $10 - \frac{5}{6} t = 0$

$10 = \frac{5}{6} t$

Therefore, $t = \frac{6 * 10}{5}$

$t = \boxed{12}$

In the above question the total time given is $14 seconds$

And the time taken for the vehicle to stop is $12 seconds$

Therefore, the driver reaction is $14 - 12$ = $\boxed{2}$

Therefore his reaction time in seconds is $\boxed{2}$ $Seconds$