A `2 kg` object is slide along the frictionless floor with intial volocity `(10 m//s) hat i` (a) Describe the motion of the object relation to car (b) when does the object reach its original position relative to the box car.

Explanation

(a) With respect to box (Non-inertial)

`x =x_(0) + u_(x)t + (1)/(2) a_(x) t^(2)`
`= x_(0) + 10t - 2.5 t^(2)`
`v_(x) = u_(x) + a_(x) t = 10 - 5t`
(b) `v_(x) = 0` at `2 s = t_(0)` (say)
:. To return to the original position time taken `= 2t_(0) = 4 s`