Is high voltage or high current more dangerous?

Is high voltage or high current more dangerous?

• A. High voltage
• B. High current
• C. High resistance
• D. Low resistance

Answer: (B)

The key idea is that harm from an electrical shock comes from the current that flows through the body. Voltage matters because it’s what pushes that current through, but the actual damage is dictated by how much current passes—through the path, for how long, and with what resistance. Ohm’s law, I = V/R, shows why this is: for a given voltage, lower resistance (which can happen with wet skin or a conductive path) yields larger current, while higher resistance reduces current. Since higher current through the body is what drives dangerous effects like muscle contractions, burns, or heart rhythm disruption, the amount of current is the best predictor of harm. The other ideas—high resistance or low resistance—describe conditions that affect current, not the danger itself; high resistance tends to limit current, making shocks less dangerous, while low resistance can allow more current to flow and be more hazardous. So the most dangerous factor to consider is the current.

The key idea is that harm from an electrical shock comes from the current that flows through the body. Voltage matters because it’s what pushes that current through, but the actual damage is dictated by how much current passes—through the path, for how long, and with what resistance. Ohm’s law, I = V/R, shows why this is: for a given voltage, lower resistance (which can happen with wet skin or a conductive path) yields larger current, while higher resistance reduces current. Since higher current through the body is what drives dangerous effects like muscle contractions, burns, or heart rhythm disruption, the amount of current is the best predictor of harm. The other ideas—high resistance or low resistance—describe conditions that affect current, not the danger itself; high resistance tends to limit current, making shocks less dangerous, while low resistance can allow more current to flow and be more hazardous. So the most dangerous factor to consider is the current.