By Ohm's Law, V = ?

**The reasoning** Ohm's Law states that **voltage (V) is directly proportional to current (I) when resistance (R) is constant**. The formula is: **V = IR** This means: Voltage = Current × Resistance Think of it like water flowing through a pipe. Voltage is the pressure pushing water, current is the flow rate, and resistance is how narrow the pipe is. More resistance or more current means you need more pressure (voltage) to push through. If you know any two values, you can find the third by rearranging: - V = IR (voltage) - I = V/R (current) - R = V/I (resistance) **Why the wrong options tempt you** - **A) I/R** — This would give you current divided by resistance, which actually equals V/V = nothing useful. Students confuse division and multiplication. - **C) I²R** — This is the formula for **power loss** (P = I²R), not voltage. Easy to mix up! - **D) R/I** — Completely backwards. Gives units that don't match voltage. **Quick takeaway** "**V equals IR**" — Voltage is current *times* resistance, not divided. Say it three times and link it to: more resistance needs more voltage to push the same current.