(adsbygoogle = window.adsbygoogle || []).push({}); Uniformly accelerated motion-- a weird kangaroo prob

Ok, I have this simple Question:

A kangaroo can jump straight up 2.5 m -- what is its takeoff speed?

How can I solve that given just one variable. Well, I know that Vi=0, right?

Also, if you anyone can help me try to solve this one?:

A car in an auto accident left skid marks 290 m long. Assuming an average acceleration of -3.9 m/s/s (that is, -0.4 g), calculate the Jag's speed when the brakes locked.

I know acceleration and scalar distance, but I don't know anything about the initial speed and such. So how can I choose a formula?

Please Help.

Thanks

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# Homework Help: Uniformly accelerated motion- a weird kangaroo prob

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