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

A motorcyclist starts from rest at a pointOand travels in a straight line. His velocity aftertseconds isvms^-2, for 0 =<t=<T, wherev= 7.2t- 0.45t^2. The motorcyclist's accelaration is zero whent=T.

Find the value ofT.

2. Relevant equations

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3. The attempt at a solution

S = X

U = 0

V = 7.2t - 0.45t^2

a = 0

t = t

v = u + at

7.2t^2 - 0.45t = 0

0.45t(t - 16) = 0

Therefore t = 0 or 16

But the answer is 8.. I believe I'm getting the accleration part incorrect but I just cannot spot it.

Please help - thank you :)

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# Mechanics : Equations of motion.

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