Question

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.

Answer 1

Answer:Initial velocity =u = 0

Distance =s = 400 m

time = t= 20 sec

a = acceleration

Equation of motion :-

s = ut + 1/2at²

400 = 0 + 1/2 × a × 20 × 20

400 = 200 a

a = 2

acceleration = a = 2 m/s²

============================

Force = F

Mass = m = 7000 kg

Acceleration = a = 2 m/s²

F = ma

= 7000 × 2

= 14000 N

Force acting on it is 14000 N

Explanation:Hope this helps u plz mark me as the brainliest

Answer 2

$\bf{\underline{\underline{Answer:}}}$

∴$\: \bf 14000\: N$

$\bf{\underline {Given:}}$

$⟹Initial\: velocity \:of \:truck\:, u=0$

(since, truck starts from rest)

$⟹ Distance\: travelled, \:s = 400\: m$

$⟹Time, \: t = 20\: s$

$\bf{\underline {To\:Find:}}$

$⟹Acceleration, a=\:?$

$\bf{\underline{\underline{Step\: by\: step \:explanation:}}}$

We know that,

$⟹s=ut+\dfrac{1}{2}at^2$

$⟹400 =0×20+\dfrac{1}{2}×a×{(20)}^{2}$

$⟹400 =0+\dfrac{1}{2}×a×400$

$a=\dfrac{400}{200}=2\:m\:s^{-2}$

Force acting upon truck,

Mass of truck = 7 tonnes = 7 × 1000 kg = 7000 kg

We know that,

Force, $F = m × a$

Therefore, $F=7000×2\:kg\:m\:s^{-2}$

Or$\:\:\:\:\:\:\:\:\:\:F = 14000 \:Newton$

Thus, acceleration of the truck is $</strong><strong> </strong><strong>\</strong><strong>bf</strong><strong> 2 \:m\:s^{-2}$ and force acting upon truck in the given condition is 14000 N.