Question

A car starts accelerating with an acceleration of `(1)/(3)m//s^(2)` when its speed was `18 km//h`. If the desplacement of car in `n^(th)` minute after it starts accelerating is `4.8km` then n is :

Answer 1

Correct Answer - 4
A car starts ………..
`Acc = (1)/(3)m//s^(2) = (60xx60)/(3)m//min^(2) = 1800m//min^(2)`
initially velocity `18 km//h = (18000)/(60) = 300m//min`
`4800=300+(1800)/(2)(2n-1)`
`(2xx4500)/(1800) = 2n-1`
`implies n = 3`