first off, i dont completely understand what do the variables in the equation do:
A body is thrown up vertically, it passes trough the height 9,8m twice. Time between those two passes is 4 seconds. Whats the starting velocity ?
The Attempt at a Solution
i presume i have to do it with two equation systems? first off i'd have to calculate the starting velocity needed to get up and down in four seconds. Then i'd calculate the starting speed needed to get to the "seconds starting speed" at 9,8m and that would be the answer.