Question

Correct form of Ohm's law is

• A. I=VR
• B. V $\propto$ I
• C. V=I/R
• D. P=I$^2$/R

Hint:

To remember the three variations of the formula, use the "V-IR" triangle. Cover the letter you want to find: cover V to see $I \times R$, cover I to see $V/R$, and cover R to see $V/I$.

Answer 1

The Correct Option is B

Ohm's law is a fundamental principle in electromagnetism that describes the relationship between voltage, current, and resistance in an ideal conductor. 1. Fundamental Statement: The law states that the current ($I$) flowing through a conductor between two points is directly proportional to the voltage ($V$) across the two points, provided all physical conditions (like temperature) remain constant. This is mathematically expressed as: $$V \propto I$$

2. The Constant of Proportionality: To convert this proportionality into an equation, we introduce a constant called Resistance ($R$): $$V = I \times R$$

3. Analyzing the Options:

• Option 1 ($I=VR$): Incorrect. According to the formula, $I = V/R$.

• Option 2 ($V \propto I$): Correct. This represents the primary statement of the law.

• Option 3 ($V=I/R$): Incorrect. The correct relation is $V = IR$ or $R = V/I$.

• Option 4 ($P=I^2/R$): Incorrect. This is a variation of Joule's law for power, where $P = I^2R$.
Therefore, the most accurate representation of the law's proportionality is $V \propto I$.