Physics
posted by Lauren .
A rock is dropped from a height of 100m.
a) how long does it take to fall the first 50m?
b)How long does it take to fall the last 50m?
Which equation would I use to solve this problems with?
For a) use s=(1/)g*t^2 where s=50m and g=9.8m/s^2 and solve for t.
For b)use s=(1/)g*t^2 where s=1000m and g=9.8m/s^2, solve for t and subtract the result of part a).
You use the same formula, but you look at the total time minus some partial time. Does that make sense?

A stone propelled from a catapult with a speed of 50ms attains a height of 100m calcutate
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