Low voltage can injure if the ______ is high enough.

Low voltage can injure if the ______ is high enough.

• A. Current
• B. Voltage
• C. Resistance
• D. Frequency

Answer: (A)

Current through the body determines injury risk. Voltage is just the potential energy that can push current, but what actually causes harm is how much current flows through you. According to I = V/R, the amount of current depends on both the voltage and the body's resistance. Wet or damaged skin lowers resistance, so even a low voltage can produce a dangerous current. Once the current reaches certain levels—think a few milliamperes for perceptible shocks, tens of milliamperes for painful or hard-to-let-go shocks, and around 100 mA or more through the heart for dangerous rhythm disturbances—injury or serious harm can occur. So the key idea is that the current magnitude flowing through the body is what determines whether there will be injury. Voltage and resistance matter only because they influence that current. Frequency has effects too, but it is the current that directly drives the injury risk.

Current through the body determines injury risk. Voltage is just the potential energy that can push current, but what actually causes harm is how much current flows through you. According to I = V/R, the amount of current depends on both the voltage and the body's resistance. Wet or damaged skin lowers resistance, so even a low voltage can produce a dangerous current. Once the current reaches certain levels—think a few milliamperes for perceptible shocks, tens of milliamperes for painful or hard-to-let-go shocks, and around 100 mA or more through the heart for dangerous rhythm disturbances—injury or serious harm can occur. So the key idea is that the current magnitude flowing through the body is what determines whether there will be injury. Voltage and resistance matter only because they influence that current. Frequency has effects too, but it is the current that directly drives the injury risk.