I need some help with this mechanics question please,(adsbygoogle = window.adsbygoogle || []).push({});

A ball is thrown vertically upwards with speed 10ms/s from a point 2m above horizontal ground.

a) calculate the length of time for which the ball is 3m or more above the ground.

b) calculate the speed with which the ball hits the ground.

so..i think i have to use the equation s=ut + 1/2 at^{2}

u= 10

a= -9.8

but i'm confused about s, should it be 2m or 3m?

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# Homework Help: Calculate the speed with which the ball hits the ground

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