A truck starts from rest and rolls down a hill with a constant acceleration. It travels a distance of 400 m in 20 s. Find its acceleration. Find the force acting on it if it’s mass is 7 metric tonnes (Hint: 1 metric tonne = 1000 kg.)

Given, distance covered by the truck (s) = 400 meters

Time taken to cover the distance (t) = 20 seconds

Initial velocity of the truck (u) = 0
{since it starts from rest}

We know that, \( s = ut + \frac{1}{2} at^2 \)

\(\therefore \) \( 400 = 0 × 20 + \frac{1}{2} (a)(400) \ = \ 2 m/s^2 \)

Now, force = mass × acceleration

\(\therefore \) force acting on truck = 7000 × 2 = 14000 N