A car is standing 100 m behind a bus. The bus and the car both start moving simultaneously with acceleration of `4 m//s^2` and `2 m//s^2` respectively. Find the time after which the car will be able to catch the bus.

Options

A. 10 s
B. 20 s
C. 15 s
D. none

Answer

A

Explanation

By the time the car meets the bus, the car has travelled 100 m extra along with the distance covered by bus.
`100 + 1/2 xx 2 xx t^2 = 1/2 xx 4 xx t^2`
`implies t^2 = 100`
`implies t = 10`