Which factor is inversely related to the amount of harm in an electrical exposure?

Which factor is inversely related to the amount of harm in an electrical exposure?

• A. Voltage
• B. Body resistance
• C. Current
• D. Frequency

Answer: (B)

The amount of harm from an electrical exposure is governed mainly by the current flowing through the body. Ohm’s law I = V/R shows that for a given applied voltage, increasing the body’s resistance reduces the current. Since the injury potential scales with current, higher resistance means less current and less harm. That’s why body resistance is inversely related to the harm. Voltage, on the other hand, tends to raise current if the resistance is fixed, so increasing voltage would generally increase harm rather than reduce it. Current itself is the direct cause of injury, so it is not inversely related to harm. Frequency can alter impedance somewhat, but it doesn’t establish the straightforward inverse relationship with harm in the way that resistance does; the dominant, practical relationship used in safety is that higher resistance lowers the current and thus the hazard.

The amount of harm from an electrical exposure is governed mainly by the current flowing through the body. Ohm’s law I = V/R shows that for a given applied voltage, increasing the body’s resistance reduces the current. Since the injury potential scales with current, higher resistance means less current and less harm. That’s why body resistance is inversely related to the harm.

Voltage, on the other hand, tends to raise current if the resistance is fixed, so increasing voltage would generally increase harm rather than reduce it. Current itself is the direct cause of injury, so it is not inversely related to harm. Frequency can alter impedance somewhat, but it doesn’t establish the straightforward inverse relationship with harm in the way that resistance does; the dominant, practical relationship used in safety is that higher resistance lowers the current and thus the hazard.