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

Data Collected on a Race by a Dragster

Distance (m) - 20.0 when Time (s) 0.945

Distance (m) - 400.0 when Times (s) 8.96

What is the acceleration of the dragster from the 20.0-m mark to the 400.0m mark?

(The answer book says 1.27m/s2 but i don't know how to get it )

2. Relevant equations

v=d/t

d= initial velocity*t+1/2at^{2}

3. The attempt at a solution

v=20/0.945

v=21.16 m/s

(2(d-(initial velocity *t)))/t^{2}= a

(2(380-(21.16*8.02))/8.02^{2}= a

(2*211.10)/64.32 = a

6.56m/s^{2}

i know the reason why im doing this wrong is because im using average velocity instead of using the initial velocity but i don't know how to find instantaneous velocity without a graph and i have too little information to draw one

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# Homework Help: How do you find Acceleration when given Distance and Time?

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