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This equation doesn't seem to be correct. Dimensionally inconsistent, in fact! How then, is it established? $$s_{t}=v_{0}+\frac{1}{2}a(2t-1)$$ (In case you don't know, this is the equation used to measure displacement in $t^{th}$ second.)

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    $\begingroup$ The right side needs to be multiplied by $\Delta t=1$ second. It was presumably omitted because “it’s just 1”, but this is a very confusing thing to do. $\endgroup$ – G. Smith Jun 18 at 4:22
  • $\begingroup$ And the $-1$ is really $-\Delta t$. $\endgroup$ – G. Smith Jun 18 at 4:32
  • $\begingroup$ Are you actually using a textbook that writes equations like this? $\endgroup$ – G. Smith Jun 18 at 4:35
  • $\begingroup$ ... Yep. That's a third world country physics textbook for you. Pretty ‘commercial’, and doesn't focus on conceptual understanding at all. Seriously tho, to average students here, Physics = Math. $\endgroup$ – Amanda Macaurenni Jun 18 at 4:41
  • $\begingroup$ So do you understand now how to get the formula by taking the difference of the displacement at time $t$ and at time $t-\Delta t$, using formulas for constant acceleration? $\endgroup$ – G. Smith Jun 18 at 4:45

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