What Happens When a Person Touches a Live Wire?

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When a person with a resistance of 13.0 kiloohms touches a live wire with a power supply of 16.0 V and an internal resistance of 2100 ohms, the current through their body can be calculated using the formula I = V/(R_p + R_i), resulting in a current of 1.06×10−3 A. For power dissipation, the correct approach involves determining the voltage drop across the person's body rather than using the total voltage of the circuit. The initial calculation of power using P = I*V is incorrect because it applies the full voltage instead of the voltage drop across the individual’s resistance. The discussion highlights the importance of correctly identifying the voltage relevant to the specific part of the circuit. Understanding these principles is crucial for accurately assessing electrical safety and effects on the human body.
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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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I think V isn't 16 V, since you want the voltage drop across his body, not the whole circuit
 

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