Answer:
The minimum current needed to stop a human heart at 120 volts AC is represented by option C) 50 mA.
Step-by-step explanation:
The minimum current required to stop a human heart is a critical parameter in electrical safety, particularly in scenarios involving exposure to AC voltage. The key factor here is the relationship between current, voltage, and the impact on the human body.
At 120 volts AC, the threshold for inducing fibrillation, which can lead to cardiac arrest, is typically around 50 mA. This means that if a person comes into contact with a current of 50 mA or higher at 120 volts AC, there is a significant risk of the heart stopping.
It's essential to recognize that the human body's resistance to electric current can vary, and factors such as skin condition and moisture can influence the level of danger. However, in standard safety assessments, the 50 mA threshold at 120 volts AC is a widely accepted reference point for potential cardiac risks. This emphasizes the importance of electrical safety measures and adherence to regulations to prevent incidents that could lead to severe health consequences.