(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A ball is thrown vertically upwards at 5 m / s from a roof top of 100m. The ball B is thrown down from the same point 2s later at 20 m / s. Where and when will they meet.

2. Relevant equations

S = So + ut + 1/2at^2

3. The attempt at a solution

well at first I separated the fact that while ball B falls at say t seconds, ball A's time is given by t+2 (due to it being thrown 2 seconds prior to ball B).

given what's given above (the velocity and height)...I wrote down the following equations to find TIME, where lower a and b denote ball A and B:

Sa = Soa + ua(t+2) + 1/2a(t+2)^2

Sb = Sob + ubt + 1/2at^2

but i tried equalizing the above two equations with all the proper variables replaced by the values provided in the problem, but unfortunately i don't get the right answer.

I'm lost, I'm not even sure if I tackled the problem correctly.

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# Homework Help: Motion of two balls

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