Deriving the Equation for Final Velocity Using Kinematic Equations

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The discussion focuses on deriving the final velocity equation, v_f^2 = v_i^2 + 2aΔd, using kinematic equations. The derivation begins with the basic kinematic equations, v = v_o + at and r = r_o + v_o*t + (1/2)at^2. By isolating time (t) from the first equation and substituting it into the second, the algebra leads to the desired equation. The process emphasizes the importance of understanding the relationships between velocity, acceleration, and displacement. This methodical approach provides a clear pathway to derive the final velocity equation.
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Homework Statement



I wanted to know how this equation is derived. Thanks.

Homework Equations



{v_{f}}^2 = {v_{i}}^2 + 2a\Delta d

The Attempt at a Solution



v_{f} - v_{i} = \frac {\Delta d a} {\Delta v}
 
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We have the two relations:
t=\frac{v-u}{t}
s=\frac{1}{2}(u+v)t

Substitute the first into the second and the deed is done.
 
Start from:
1. v=vo+at
2. r=ro+vo*t+(at^2)/2
Find t from 1 and replace in 2, do all the algebra and you are done.
 
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