Calculating Current in a Circuit

AI Thread Summary
The problem involves calculating the current through a 5-ohm resistor with a 20V potential difference. The correct calculation is 20V divided by 5 ohms, which equals 4 A, as the unit for current is amperes (A). The initial response incorrectly stated the result as volts instead of amperes. It's important to clearly show the equation before substituting values to avoid confusion. Accurate unit representation is crucial in circuit calculations.
wakejosh
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Homework Statement


you measure a 20v potential difference across a 5 ohm resistor. what is the current?

The Attempt at a Solution


20 v/5 ohms = 4 v

is this correct? thanks.
 
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No, not correct; your units are wrong
(why would a volt divided by an ohm be a volt?)
And, if you're looking for current, what is the SI unit for current?

Otherwise, it's fine. Personally, I prefer to see the equation you used before you plug in values.
 
typo, meant to put:

20 V / 5 ohms = 4 A
 

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