(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A speed skater crosses the start line of a straight 200m downhiull course with speed of 30m per second. She accellerated uniformly all the way down taking 5 sec to cover the course - what is her speed at the finish line? I know this should be simple, but just can't get the answer to work out the same as the solution in the paper.

2. Relevant equations

s = 1/2 (u+v)t

3. The attempt at a solution

200 = 1/2 (30+v)5

200/5 = 1/2(30+v)

40 = 1/2(30+v)

2 x 40 = 30 + v

80 - 30 = v

v = 50m per sec

Answer in book is 45 - HOW??????????????????

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# Equations of Motion question

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