What is the lowest voltage that can potentially cause death?

• A. 24 Volts
• B. 30 Volts
• C. 120 Volts
• D. 240 Volts

Answer: (B)

The danger comes from the current that can flow through the body, not just the voltage alone. Current through the heart is what can cause fatal rhythms, and how much current flows depends on the body's resistance and the duration of exposure. Ohm’s law says current = voltage divided by resistance, so lower resistance (like wet or damaged skin) means more current for the same voltage.

Under dry conditions, the body's resistance is high, so voltages in the 24–30 volt range generally don’t push dangerous current. But when skin is wet or there’s a path through moist tissue, resistance drops, and a voltage as low as 30 volts can drive enough current to be dangerous, especially if exposure is prolonged or the current takes a path through the chest.

So among the options, 30 volts is the lowest voltage listed that could potentially cause a fatal shock under adverse conditions. Higher voltages like 120 or 240 volts are obviously hazardous, while 24 volts is typically unlikely to be lethal in normal dry conditions.