Question

A truck starts from rest and Rolls down a hill with a constant acceleration it travels a distance of 400m in 20 seconds find its acceleration find the force acting on it if its mass is 7000 kg?

Answer 1

Given:-

m = 7000kg

S = 400m

u =0

t = 20s

To Find:-

a = ?

Solution:-

By second equation of motion,

$\sf s = ut + \frac {1}{2} \times a \times {t}^{2} \\ \\ \sf \implies 400 = 0 \times 20 + \frac{1}{2} \times a \times {20}^{2} \\ \\ \sf \implies 400 = 200a \\ \\ \sf \implies a = 2 \frac{m}{ {s}^{2} }$

we have,

the formula used here

$\sf f = ma \\ \\ \sf f = 7000 \times 2 kg\frac{m}{ {s}^{2} }$

$\sf{14000N}$

Hence，acceleration is 14000N.