Question

a truck starts from rest and Rolls down a hill with a constant acceleration. It travels a distance of 400 metre in 20 second find its acceleration​

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,

$s = ut + \frac{1}{2} a {t}^{2}$

$400 = 0 + \frac{1}{2} a \times {(20)}^{2}$

a = 2m/s^2

Answer 2

Explanation:

$\textsf{Given}$

$\implies \textsf{u = 0 }\\ \textsf{ s = 400 \:m }\\ \textsf{ t = 20\:s }$

$\mathrm{s = ut +\frac{1}{2} a {t}^{2}}$

$\mathrm{400 = 0 + \frac{1}{2} a( {20})^{2}}$

$\mathrm{a = \frac{400 \times 2}{400}}$

$\textsf{a = 2}$

$\mathrm{Therefore,\:acceleration\: of\: truck\: is\:2m/s^2}$

Acceleration(a) :- When the body change its velocity with time is said as acceleration.

S.I unit m/s^2

Distance :- It is the length of actual path covered by the body between its initial and final position.