Why voltage in a short circuit is 0?

[alexmath]

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!

 

[darkxponent]

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 infinite 0/0 is finite.

 

[mfb]

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.

 

[technician]

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.

 

[Nickie]

In a short circuit, the resistance drops to almost zero, causing a very high current to flow through the circuit. This high current can cause damage to the circuit and can be dangerous. However, according to Ohm's law, voltage (U) is equal to current (I) multiplied by resistance (R). In the case of a short circuit, R is extremely small, and as a result, U also becomes very small. This means that the voltage in a short circuit is close to zero.

The reason why 0 "wins" in this scenario is because the resistance is so low that it essentially "overrides" the voltage. As the resistance approaches 0, the voltage also approaches 0, making it the dominant factor in the equation. It is important to note that even though the voltage may be close to 0 in a short circuit, the current can still be very high and dangerous. This is why it is important to have safety measures in place to prevent short circuits from occurring.