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

A rock is rolled in the sand. It starts at 5.0 m/s, moves in a straight line for a distance of 3.0m and then stops. What is the magnitude of the average acceleration?

2. Relevant equations

aavg = change in V/ change in time

magnitude of acceleration = change of speed/time interval.

3. The attempt at a solution

i think i am thinking too hard about this problem. seems simple but cannot get the right answer

found time = 1.67 s and tried to plug in for average acceleration. 5.0/1.67 = 2.99 m/s^2

the correct answer is 4.2 m/s^2.

?? can't figure out what i am doing wrong.

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# Homework Help: Laws of motion magnitude of average acceleration

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