Power and Resistance in Electrical Circuits

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SUMMARY

The discussion centers on calculating the current through a person's body when exposed to a power supply with a potential difference of 16.0 V and an internal resistance of 2100 ohms, alongside the person's resistance of 13.0 kiloohms. The correct current calculation using the formula I = V/(R_p + R_i) yields a current of 1.06×10−3 A. However, the power dissipated in the body was incorrectly calculated using P = I*V, which does not account for the correct voltage across the person's resistance. The power should be calculated using P = I^2 * R.

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Suppose that a person has a resistance of 13.0 kiloohms as part of a circuit which passes through his hands. This person accidentally grasps the terminals of a power supply with a potential difference of 16.0 V.
PART A:If the internal resistance of the power supply is 2100 ohms , what is the current through the person's body?
I calculated the current to be 1.06×10−3 A by using the equation I = V/(R_p + R_i)
PART B: To find the power dissipated in his body I thought you use the equation P = I*V so P =(1.06*10^-3 A)*(16.0V) which gave me 1.70*10^-2 which is wrong. What I am doing wrong??
Thank you for your help
 
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You assumed that the 2 resistances are in series. Are they?
 
I noticed the same post in the Intro Physics section. You should avoid double posts.
 

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