Question

What can a shock of more than 50 mA do to a person?

1) Cause severe burns
2) Cause muscle contractions and difficulty breathing
3) Cause cardiac arrest
4) All of the above

Answer 1

A shock of more than 50 mA can lead to muscle contractions, difficulty breathing, cardiac arrest, and severe burns, depending on the current level and concentration.

Step-by-step explanation:

A shock of more than 50 mA can cause severe effects on a human body, including muscle contractions, difficulty breathing, and the potential for cardiac arrest. At currents between 10 to 20 mA, the person may experience sustained muscle contractions and the 'can't let go' effect, where the muscles that close the fingers are stronger than the muscles that open them, causing an involuntary grip.

At levels between 100 and 300 mA, cardiac arrest may occur due to ventricular fibrillation, where the heart beats irregularly and ineffectively, which can be fatal without immediate medical intervention. Additionally, at about 300 mA and above, the likelihood of severe burns increases significantly, especially where the current is most concentrated.