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

Two physics students are trying to determine the instantaneous speed of a bicycle 5m from the start of a 1000m sprint. They use a stopwatch to measure the time taken for the bicyble to cover the first 10m. If the acceleration was constant, and the measured time was 4sec, what was the instantaneous speed of the bicyle at 5m mark?

2. Relevant equations

3. The attempt at a solution

Method 1:

Find acceleration:

a=change in velocity/change in time

=(displacement/time) /time

= displacement/time^2

= (10-0)/(4-0)^2

=.625m/s^2

Find instantaneous velocity at 5sec:

5 x .625 = 3.125m/s

BUt the answer is wrong. WHy?

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# Simple motion prob.

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