Question

Voltage across a short circuit is:

• A. Zero
• B. Infinite
• C. Changing between zero and infinite
• D. Unity

Hint:

Short circuit → zero resistance → zero voltage drop.

Answer 1

The Correct Option is A

In the field of instrumentation engineering, understanding the behavior of electrical circuits is crucial. One fundamental concept is the voltage across a short circuit. To comprehend why the voltage is zero, let's consider the properties of a short circuit:

• A short circuit occurs when there is a direct connection between two points in a circuit, typically through a conductor with negligible resistance.
• In a theoretical sense, resistance in a short circuit is zero ohms.
• Using Ohm’s Law, which states \( V = I \times R \), where \( V \) is voltage, \( I \) is current, and \( R \) is resistance, we can analyze the voltage across the short circuit.

Calculation:

• Given \( R = 0 \) (since it's a short circuit), substituting in Ohm’s Law gives \( V = I \times 0 = 0 \).

Even if the current \( I \) is infinite due to the lack of resistance, any multiplication with zero results in zero voltage.

Hence, the voltage across a short circuit is always zero.

The correct answer is: Zero