Typed it wrong
A stone is thrown vertically upward at a speed of 30.30 m/s at time t=0. A second stone is thrown upward with the same speed 2.500 seconds later. At what time are the two stones at the same height?
At what height do the two stones pass each other?
What is the upward speed of the second stone as they pass each other?
H1 = 30 t - 4.9 t^2
H2 = 30 (t-2.5) - 4.9(t-2.5)^2 = 30 t - 75 - 4.9(t^2 - 5 t + 6.25)
= 30 t - 75 - 4.9 t^2 + 24.5 t - 30.625
so when H1 = H2
0 = -75 + 24.5 t - 30.625
24.5 t = 105.6
t = 23.5 seconds
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