I am wondering how is the third equatio of motion derived, I was reading a text on my physics course which it is very unclear how they exactly they arrived to this equation, knowing this from the book, using the equations for velocity and position, you can combine them to get 3 new equations of motion, I know this equations are important to know because I recently got stuck on a question and would have never know to use the third equation to find an correct answer(adsbygoogle = window.adsbygoogle || []).push({});

Third Equation Of Motion

[itex]v^2 = v_{0}^2 + 2ax[/itex]

v = final velocity, v_0 = initial velocity, a = acceleration x = position

Said equations from text to be "combined" and with eliminated the variable, t, time to arrive at the velocity equation above

[itex] v = v_0 + at[/itex]

[itex] x = v_{0}(t) + \frac{at^2}{2}[/itex]

I know there just some simple algebra being used here, but someone who has just general knowledge of the motion of along a straight plane equations of the sort, more specifically, acceleration, velocity, position, going into a physics course for the first time how do you know when/which "extra" equation to use?

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# Third Equation Of Motion Question

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