A student with wet hands accidentally touches a bare wire connected to 120 V. If the student's body resistance is 1350 amps, and muscles contract above 20 mA, will the student be able to let go?

Question

theeric · Answer

@hissae2 , is the body resistance in amps, or is it in Ohms? Ohms might look like "$\Omega$"

anonymous · Answer

Oh sorry, it is Ohms

theeric · Answer

Not a problem! So, have you learned the popular version of Ohm's law?
$V=I\ R$
?

anonymous · Answer

Yes

theeric · Answer

Alright! Well now you need to apply it! So, you have 120V and 1350$\Omega$. What ARE those?
Hint: they are either
Voltage (V)
Resistance (R)
or
Current (I)

anonymous · Answer

120v is voltage, 1350ohms is resistance

theeric · Answer

Right! And so you can find the current with Ohm's law. What is the resulting current?

anonymous · Answer

I got 0.0888

theeric · Answer

Looks good! So that's the current going trough your muscles. What does that look like in milliamps?

anonymous · Answer

88.88

theeric · Answer

Yup!! So the current through your muscles is 88.88 mA.

If that over 20mA, your muscles contract.
If that is under 20mA, your muscles don't contract.

So, do you have your answer now?

anonymous · Answer

It's over 20mA so won't be able to let go. Makes sense. Thank you for all the help :)

theeric · Answer

Awesome! You're welcome! :)