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 tonnes (Hint: 1 tonne = 1000 kg.)

Asked by Vishal kumar | 2 years ago |  231

1 Answer

Solution :-

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 a state of rest)

From the equations of motion, \(s\,=\,ut+\frac{1}{2}at^2\)

 \(Therefore,400 = 0(20s) + \frac{1}{2}(a)(400s^2) = 2ms^{-2}\)

The acceleration of the truck is equal to 2ms-2

As per the second law of  motion, force = \(Mass\,\times\,Acceleration\)

Mass of the truck = 7 tonnes = 7000 kg

Force acting on the truck = 7000 kg \( \times\) 2 m.s-1 = 14000 kg.m.s-2 = 14000 N

Therefore, a force of 14000 N is acting on the truck.

Answered by Shivani Kumari | 2 years ago

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