Dimensional Analysis Equation Help

AI Thread Summary
The discussion focuses on determining the dimensional correctness of two equations: (a) v^2 = v^2 + 2at and (b) v^2 = v^2 + 2ax. The analysis reveals that equation (a) is incorrect because the term 2at results in dimensions of [L]/[T], which does not match the dimensions of the other terms. In contrast, equation (b) is correct as all terms have consistent dimensions of [L]^2/[T]^2. The key takeaway is that for dimensional analysis, all terms in an equation must share the same dimensions for the equation to be valid.
Manda*n
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Homework Statement



The question states which of the following equations are dimensionally correct?
(a) v^2=v^2+2at or (b) v^2=v^2+2ax

Homework Equations


v=[L]/[T], x=[L], a=[L]/[T]^2


The Attempt at a Solution


(a) v^2=v^2+2at
[L]^2/[T]^2=[L]^2/[T]^2+([L]/[T]^2)([T])
[L]^2/[T]^2=[L]^2/[T]^2 + [L]/[T]

(b)v^2=v^2+2ax
[L]^2/[T]^2=[L]^2/[T]^2+([L]/[T]^2)([L])

The correct answer listed is b.. I just don't understand why a is incorrect while b is correct.
Can someone please explain? Thanks!
 
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(a) v2=v2+2at
[L]2/[T]2=[L]2/[T]2 + [L]/[T]

The last term [L]/[T] is not squared like the other two.

(b)v2=v2+2ax

[L]2/[T]2=[L]2/[T]2+([L]/[T]2)([L])

The last term

([L]/[T]2)([L])=([L]2/[T]2)

and this is of the same dimensions as the other two terms.
 
So Simple! Thank you so much.
 
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