Question

A truck starts from rest and rolls down a hill with a constant acelleration. It travels a distance of 400m in 20s. Find the acelleration. Find the force acting on the body if its mass is 7 metric tonnes.

Answer 1

The truck starts from rest, so initial velocity = 0

Distance travelled = 400 m

Time taken = 20 s

We know the equation of motion, S = ut + ½ at^2

400 = 0 + ½ a * (20)^2

a = 2 m/s2

Now, mass = 7 metric tonnes

= 7 * 1000

= 7000 kg

So force = mass * acceleration

F = 7000 * 2

= 14000 N