Question statement:
A rocket is moving in a gravity free space with a constant acceleration of 2ms−2, along + x direction (see figure). The length of a chamber inside the rocket is 4 m. A ball is thrown from the left end of the chamber in + x direction with a speed of 0.3ms−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 end relative to the rocket. The time in seconds when the two balls hit each other is__________ ?
This is a question from jee advanced. I followed the approach of relative velocity. In the frame of rocket we can write:
- $s_{rel}$=$u_{rel}t$ since acceleration of both the particles is 0 in this frame . This gives answer as 8seconds which is wrong and it is 1.9 seconds
So my question is why relative motion approach can't be used here - is there some exception to cases where relative motion can be used?