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

Heather and Jerry are standing on a bridge 50\;m above a river. Heather throws a rock straight down with a speed of 20\;m/s. Jerry, at exactly the same instant of time, throws a rock straight up with the same speed. Ignore air resistance.

How much time elapses between the first splash and the second splash?

4.08 s

2. Relevant equations

3. The attempt at a solution

i already have the answer of 4.08 s, which according to mastering physics, is correct.

question is: in solving the equations i was instructed to use a positive g for heather and a negative g for jerry........i don't get this.

maybe i did the problem wrong and got the correct answer.

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# Homework Help: Need help with the sign of g in free fall acceleration

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