Question

A current of 0.001 A can be felt by the human body. 0.005 A can produce a pain response. 0.015 A can cause a loss of muscle control. In the procedures of this lesson, over 0.030 A of current traveled in the three-battery circuit. Why was this circuit safe to handle with dry hands? Include the resistance of human skin in your answer.

Answer 1

In summary, it is safe to handle this voltage with dry hands because the current value that you pass through the body is smaller than its underestimated sensitivity.

Step-by-step explanation:

The current flowing through your system is described by Ohm's law

V = I R

where I is the current, V the voltage and R the resistance

in this case three barateras are taken in series giving a total voltage of V = 4.5 V the typical resistance values ​​of dry skin is R = 1000 000Ohm and the resinification of wet skin is R = 100000 ohm

let's calculate the current flowing

I = V / R

I = 4.5 / 1000000

I = 4.5 10⁻⁶ A

this is the current with dry hands, we see that much less than the value that allows to feel a painful response by the body

If the skin is

I = 4,5 / 100,000

I = 4.5 10⁻⁵ A

This value is small, but it is close to the pain threshold, but it is in the range of slight discomfort.

In summary, it is safe to handle this voltage with dry hands because the current value that you pass through the body is smaller than its underestimated sensitivity.