(adsbygoogle = window.adsbygoogle || []).push({}); Im having trouble with a few problems.

1.A kangaroo jumps to a vertical height of 2.5 m. How long was it in the air before returning to Earth?

? s ( On this problem I keep getting a negative number.I know that this on is wrong for sure. What equation should I be using?)

3. A helicopter is ascending vertically with a speed of 6.00 m/s. At a height of 170 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground?

?s ( I have tried three equations but I still can figure out exactly which one I should be using)

10. A stone is thrown vertically upward with a speed of 13.0 m/s from the edge of a cliff 72.0 m high

(a) How much later does it reach the bottom of the cliff?

? s

(b) What is its speed just before hitting?

?m/s

(c) What total distance did it travel?

?m

(Once again I am getting negatives!)

25. A rock is dropped from a sea cliff and the sound of it striking the ocean is heard 6.6 s later. If the speed of sound is 340 m/s, how high is the cliff?

? m (This one Im not sure what I am doing wrong)

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# Homework Help: Im having trouble with a few preoblems.

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