Question

A rocket is moving in a gravity free space with a constant acceleration of `2ms^(-1)` along +x direction (see Fig.5.126). The length of a chamber inside the rocket is 4m. A ball is thrown from the left end of the chamber in +x direction with a speed of 0.3 `ms^(-1)` relative to the rocket. At the same time , another ball is thrown in -x direction with a speed of `0.2ms^(-1)` from its right and relative to the rocket. the time in seconds when the two balls hit each other is:

Answer 1

Correct Answer - 2
Consider motion of two balls with respect to rocket.
Maximum distance of ball A from left wall
`(u^(2))/(2a)=(0.3xx0.3)/(2xx2)=(0.09)/(4)=0.02m`

So, collision of two bals will take place very near to left wall.
For `BS=ut+(1)/(2)at^(2)`
`-4=-0.2t((1)/(2))2t^(2) rArr t^(2)+0.2t-4=0`
`rArrf t=(-0.2+-sqrt(0.04+16))/(2)=1.9`
nearest integer=2s.