Question

A car starts from rest and moves down in a high hill with a constant acceleration. It travels a distance

of 300 m in 10s. Find its acceleration. Find the force acting on it if its mass is 1500 kg

Answer 1

9Kn is the answer because 1500 is kg

Answer 2

The car starts at rest and accelerates uniformly with magnitude
`a`, so the distance
`x` it travels in time
`t` is

`x = \frac12 at^2`

Solve for
`a`.

`300\,\mathrm m = \frac12 a (10\,\mathrm s)^2 \implies a = (600\,\rm m)/(100\,\mathrm s^2) = \boxed{6(\rm m)/(\mathrm s^2)}`

By Newton's second law, the magnitude of force
`F` acting on the object, if its mass
`m` is 1500 kg, is

`F = ma = (1500\,\mathrm{kg})\left(6(\rm m)/(\mathrm s^2)\right) = \boxed{9000\,\mathrm N} = 9\,\mathrm{kN}`