Deriving Big 5 Motion Laws Non-Calculus and Calculus

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The discussion focuses on deriving the five motion laws using both calculus and non-calculus methods. The user successfully derives several equations, including v = at + v0 and x = v0t + 1/2 at^2, through integration and basic definitions of acceleration. They express a desire for a calculus-based proof of the average velocity formula, vavg = (v0 + v)/2, and seek non-calculus derivations for the equation Δv^2 = 2ax. The user finds some progress with a relationship involving acceleration and velocity but remains curious about further insights into the average velocity and the last motion law. The conversation emphasizes the exploration of different derivation techniques for fundamental motion equations.
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"Simple" derivations

I set out trying to derive the big 5 motion laws not only regularly, but calculus-style:

dv=adt
Integration yields v=at + C, and thus we get v=at+v0.
Non-calculus method is just using the definition of a=deltav/deltat and is trivial.

dx=vdt
x=(v0+at)dt
x=v0t + 1/2at^2 + C, and thus x=v0t + 1/2 at^2 + x0.

dx=v0dt
x=(v-at)dt
x=vt-1/2at^2+C, and thus x=vt-1/2at^2 + x0.

vavg=xt, and vavg=(v0+v)/2...i get that because of simple math and graphing with constant acceleration, but is there a calculus way to prove this?

What are the non-calculus derivations for the two i just mentione above.
Also, the last one has completely stumped me...(deltav^2=2ax), both non-calculus and calculus methods. If you have any hints/derivations with which to enlighten me, that would be much appreciated. Thanks.
 
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quincyboy7 said:
I set out trying to derive the big 5 motion laws not only regularly, but calculus-style:

dv=adt
Integration yields v=at + C, and thus we get v=at+v0.
Non-calculus method is just using the definition of a=deltav/deltat and is trivial.

dx=vdt
x=(v0+at)dt
x=v0t + 1/2at^2 + C, and thus x=v0t + 1/2 at^2 + x0.

dx=v0dt
x=(v-at)dt
x=vt-1/2at^2+C, and thus x=vt-1/2at^2 + x0.

vavg=xt, and vavg=(v0+v)/2...i get that because of simple math and graphing with constant acceleration, but is there a calculus way to prove this?

What are the non-calculus derivations for the two i just mentioned above.
Also, the last one has completely stumped me...(deltav^2=2ax), both non-calculus and calculus methods. If you have any hints/derivations with which to enlighten me, that would be much appreciated. Thanks.

Somewhat solved. a=dv/dt=(dv/dx)(dx/dt)=vdv/dx. Then adx=vdv and ax=v^2/2 + C and so the show goes on. Wicked relieved, but still would appreciate any calculus answers to why vavg=1/2 (v0+v) and a non-calculus answer to the last rule still.
 
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