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The body fat meter assumes parallel resistance in a standard human body. One resistor is fat and the other is muscle. A voltage is applied. Lab measurement of current mechanical models shows If = 0.3 mA when it is all fat, and Im = 1 mA all muscle. A person has 16 % fat. He/she will get a current Itotal of _____ mA while holding the meter.

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Final answer:

To find the Itotal when a person with 16% body fat holds the body fat meter, the currents for fat and muscle are adjusted based on the percentage of composition and summed together, resulting in a total current of 0.888 mA.

Step-by-step explanation:

The question involves a body fat meter that uses electrical resistance to determine body composition. To calculate the total current, Itotal, when a person with 16% body fat holds the meter, we assume that the fat and muscle in the body act as resistances in parallel. Given the currents for all fat (If) and all muscle (Im), the currents can be considered to be parallel branch currents in an electrical circuit. The formula for total current in parallel circuits is Itotal = If + Im. In this specific scenario, we adjust the given currents to account for the percentage of fat and muscle.

Since the person has 16% fat, they have 84% muscle (100% - 16%). Assuming that the electrical currents through fat and muscle are proportional to their presence in the body, we multiply the currents by their respective percentages: If_adjusted = If × fat percentage and Im_adjusted = Im × muscle percentage. Therefore, we have If_adjusted = 0.3 mA × 0.16 and Im_adjusted = 1 mA × 0.84.

Calculating these values gives us If_adjusted = 0.048 mA and Im_adjusted = 0.84 mA. We then add these adjusted currents to find the total current Itotal: Itotal = If_adjusted + Im_adjusted = 0.048 mA + 0.84 mA = 0.888 mA. Hence, the person holding the meter will get a total current of 0.888 mA.

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