Power Math: Finding Current & Power Dissipated through Person

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A person with a resistance of 13.0 kiloohms grasps a power supply with a potential difference of 16.0 V, leading to a calculated current of 1.06×10−3 A using the formula I = V/(R_p + R_i). The initial attempt to calculate power dissipated in the body using P = I*V was incorrect, as it calculated power delivered by the power supply rather than absorbed by the person. The correct approach involves using the voltage across the person or applying the formula P = I^2R, which accounts for the resistance of the hands. It is noted that the resistance through a person's hands is likely higher than initially stated, potentially in the megaohm range. Understanding these distinctions is crucial for accurate power calculations in electrical circuits involving human resistance.
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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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Firstly I'd just like to comment that the resitance through a person's hand is a bit higher than that. In the mega, if not giga ohm range.

By using P = IV, you have essentiatlly calculated the power DELIVERED by the power suppy instead of the power being absorbed by the person. If you want to use P=IV, then the V must be the potential difference across the person which can be calculated using voltage division. The easier equation would be P = I^2R where you use R of the hands.
 

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