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 its mass is 7 metric tonnes (Hint. 1 metric tonne = 1000 kg).
Firstly, we will calculate the acceleration:
Given,
Initial velocity, u = 0
Distance travelled, s = 400 m
Time, t = 20 s
Acceleration, a =?
We know that,
s = ut + 
at2
400 = 0 × 20 + 
× a × (20)2
400 = 0 + 
× a × 400
400 = a × 200
a = 
a = 2 m/s2
Therefore, the acceleration of the truck is 2 m/s2
Now, we will calculate the force:
Force, F = m × a
F = 7 × 1000 × 2
= 14000 N
Therefore, the force acting on the truck is of 14000 N
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