If you are going to throw a 1kg ball vertically upward and reach a maximum height of 18m. A)How much energy is needed?(adsbygoogle = window.adsbygoogle || []).push({});

B)What should be the initial speed of the ball?

My solution:

mgh=1/2mv^2

v=√2gh

v=√2(9.8)(18)

v=18.78m/s

In getting the energy

I derived the work energy theorem

2w=vo^2

2w=18.78^2

w=176.34 joules

I'm not sure if my answer is correct so I would be extremely grateful if someone could check it.

Thanks.

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# Homework Help: How to find energy if mass and height is given?

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