Dots on physics equations. What do they mean?

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epislon58
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So when there is a dot above the equation it means with respect to time. What does it mean if there are two on the top or one on the side?
 
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Two on top of a variable usually mean the second derivative with respect to time.
"One on the side" - can you give an example?
 
That is a shorthand of writing the derivative. Two dots above would mean double derivative.

One on the side - I don't recall that one.

PS. 0405, 0406, 0408 and they all showed up with my post not before
 
epislon58 said:
So when there is a dot above the equation it means with respect to time. What does it mean if there are two on the top or one on the side?

One dot on top usually means the first derivative with respect to time (that is, speed), two dots on top the second derivative with respect to time (that is, acceleration).

A dot on the side? Show us an example of what you mean and you'll get a better answer.
 
perhaps the dot on the side - he is referring to f prime and f double prime - only thing i can think of, only it's not a dot.
 
This is what I am talking about.
 

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Well it so the Euler Lagrange equation. Is it suppose to be there ?
 
That's hard to tell from the RHS only, as both derivatives (with and without dot) are interesting.
You can check the units to find it out.
 
This is the entire equation
 

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it's just derivative wrt time


.
x = dx/dt
= lim: t→0 in x/t
 
CompuChip said:
namanjain, OP is talking about the second dot.
That's just a period marking the end of the sentence.

ohh! sorry read half of the first sentence
well 2 on top means: ..
x =
d2x
______________
dt2

second derivative

eg if
x=t8 e(t2)

a = d2x
______________
dt2

get answer using wits,(:-p it's short)

aNs

a= 56t6e(t2) + 34t8e(t2) 4t10e(t2)
 
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mfb said:
namanjain please read the full thread, you are not adding anything new here.

then i suppose discussion is over, thank you