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**1. Homework Statement**

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

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

**2. Homework Equations**

kinematic ones

**3. The Attempt at a Solution**

We I wanted to find the intial speed of the ball when it is 3 metres above the ground

i used v² = u² + 2as

and found u to be about 10.936

now do i need to find how high the ball goes from 3m above the ground to having a velocity of zero? I got 314/93. Once i find this i can I then use this in the s= ut + 0.5at² equation.

4.9t² + 10t - (314/53) = 0

I tried and i got a final answer of -1.86 when the answer in the book is 1.83

Have I done the right steps???

Thanks

Tom

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