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Jun 2, 2018 at 7:04 history edited J.G. CC BY-SA 4.0
added 12 characters in body
Jul 12, 2017 at 12:32 vote accept Pancake_Senpai
Jul 12, 2017 at 12:32 comment added Pancake_Senpai Oh right! That was a really silly mistake. Thank you.
Jul 12, 2017 at 12:26 comment added Alex S It is a big difference between the equation of motion of a mass going with constant velocity and the equation of motion of a mass going with constant acceleration. The first equation is $\Delta d=v*\Delta t$ and the last one is $\Delta d=va*\Delta t$. Again, you applied the first one, not the second. You perhaps don't realize that because $vi=0$
Jul 12, 2017 at 12:20 comment added Alex S This equation of motion is not correct. When a mass goes with a constant acceleration, the correct equation of motion is $\Delta d=va*\Delta t$, where $\Delta d$ is the difference $xf-xi$ corresponding with the final and initial coordinates of the mass, va is the average velocity $va=(vi+vf)/2$ and $\Delta t$ is the time. In your case, $va$ is not $vf$ is $vf/2$ or according to your notation is $v/2$ and you got the correct solution with $2/v$
Jul 12, 2017 at 12:11 comment added Pancake_Senpai $\frac{\Delta t}{\Delta d} = \frac{1}{\Delta v}$, but when the object starts from rest then $\Delta v = $ final velocity of particle, which I'm representing by $v$.
Jul 12, 2017 at 11:53 comment added Alex S Then you made a mistake when you said that $\Delta t/\Delta d=1/v$. This assumption would have been correct if the mass would have been going with constant velocity, but is not the case here
Jul 12, 2017 at 11:47 review First posts
Jul 12, 2017 at 12:09
Jul 12, 2017 at 11:46 comment added Pancake_Senpai In regards to both your answer and the other answer by @Steven , I understand your answers but I don't understand what I did wrong in my derivation. I must have made an error otherwise I would have had my missing $\frac{1}{2}$.
Jul 12, 2017 at 11:43 history answered Alex S CC BY-SA 3.0