Find R: Internal Resistance Equation

AI Thread Summary
To find the internal resistance r of a battery using the equation r = (E - V) / V * R, one must know the electromotive force (emf) E, the terminal voltage V, and the resistance of the voltmeter R. The discussion clarifies that R is necessary for calculating r, but the user is unsure how to determine R. Understanding the relationship between these variables is crucial for solving the equation. The focus remains on the algebraic manipulation needed to isolate and calculate the internal resistance.
heelp
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In this equation I r= E-V/V*R


How would I find R? thanks in advance you your help.
 
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What do you mean? Are you asking about how to do the algebraic manipulations? And where are the parens in your equation?
 
Oops. r= (E-V/v)*R

This equation shows that knowing the emf E, the voltmeter's reading of the terminal voltatge V, and the resistance of the voltmeter R, the unknown internal resistance r of the battery can be computed.


I'm trying to find r. I know E,AND V. But I don't know how to find R.
 
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