Does this equation have the correct units of measurement?

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Discussion Overview

The discussion revolves around the correctness of an equation related to work done, specifically examining the units of measurement involved in the equation ##dW=F^→⋅dr^→## and its comparison to the expression ##-E^→.dr^→##. Participants are analyzing whether the units balance correctly, with a focus on the implications of unit discrepancies.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants express doubt about the equation's correctness, noting that ##dW=F^→⋅dr^→## has units of joules, while ##-E^→.dr^→## is associated with volts.
  • One participant suggests that the equation may be missing a charge component, indicating that volts multiplied by coulombs equals joules.
  • Another participant emphasizes that any imbalance in units indicates an error in the equation.
  • Several posts focus on the formatting of vectors in LaTeX, with participants discussing the correct syntax for representing vectors.

Areas of Agreement / Disagreement

Participants generally disagree on the correctness of the equation, with multiple competing views regarding the units and the necessity of including charge. The discussion remains unresolved.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the units and the definitions of the terms involved. The mathematical steps leading to the conclusions about unit balance are not fully explored.

gracy
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I have seen this in my book.Is this equation correct
##dW=F^→⋅dr^→##=##=-E^→.dr^→##
I don't think it is correct because ##dW=F^→⋅dr^→##
has unit of joule whereas ##- E^→.dr^→## it's unit is volt.
 
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gracy said:
I have seen this in my book.Is this equation correct
It's hard to read, but I think it misses charge. V*C=J
 
gracy said:
I have seen this in my book.Is this equation correct
##dW=F^→⋅dr^→##=##=-E^→.dr^→##
I don't think it is correct because ##dW=F^→⋅dr^→##
has unit of joule whereas ##- E^→.dr^→## it's unit is volt.

Any time the units don't balance you know something is wrong somewhere.

By the way, in Latex, \vec{E} will appear as ##\vec{E}##... Often useful when working with vectors.
 
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And if you want to make a vector out of a single letter like E, the curly braces are optional. \vec E works just as well to produce ##\vec E##. You need the braces only when the symbol is more than one character, e.g. \vec {AB} gives you ##\vec {AB}##. \vec AB on the other hand gives you ##\vec AB##.
 
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/vec{F}
 
/vec{F}
 
##/vec{F}##
 
I am not able to write vectors.
 
gracy said:
##/vec{F}##
You have to use the backslash \, not the front slash/.
##\vec{F}##
 
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  • #10
\vec{F}
 
  • #11
gracy said:
\vec{F}
And the ## before and after.
 
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  • #12
##\vec{F}## PERFECT!
 

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