# Why voltage in a short circuit is 0?

Why voltage in a short circuit is 0?

I=U/R , R goes to 0, I goes to infinity => U=IR= 0 times infinity, i don't get it, why 0 "wins" here? Thank you!

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Why voltage in a short circuit is 0?

I=U/R , R goes to 0, I goes to infinity => U=IR= 0 times infinity, i don't get it, why 0 "wins" here? Thank you!
R goes to zero correct. So U must be zero so that current is finite. 1/0 is infinte 0/0 is finite.

mfb
Mentor
In real circuits, I is always limited in some way (by the power supply, for example). Usually this is more important than the tiny resistance of wires.

Voltage is a measure of how much energy is needed to move charge from one point to another.
If the resistance is zero then no energy is needed.
Understanding of physics is the explanation, don't get tied up multiplying and dividing zeros and infinities.