How much power is radiated by the human body?

In summary, the power per unit area radiated by an ideal blackbody radiator is given by P/A = σT^4, where P = power, A = surface area, σ = 5.67 ×10−8 W m−2 K−4 is the Stefan-Boltzmann constant, and T = temperature in absolute kelvin scale. The total power radiated by a blackbody cylinder of height 1.22 m and radius 0.15 m at human body temperature can be calculated using this formula, but the result will be considerably higher than the power radiated by a human body, as human skin is not a good radiator in the infrared.
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maikeemi
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The power per unit area radiated by an ideal blackbody radiator is P/A = σT4, where P = power, A = surface area, the Stefan-Boltzmann constant is σ = 5.67 ×10−8 W m−2 K−4, and T = temperature (in the absolute kelvin scale).

How much power is radiated by the human body? Calculate the total power radiated by a blackbody cylinder of height 1.22 m and radius 0.15 m at human body temperature. (Ignore radiation from the ends of the cylinder.) (The result is considerably more than the power radiated by a human body, because skin is not a good radiator in the infrared.)
 
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Related to How much power is radiated by the human body?

1. How is power measured in the human body?

Power in the human body is typically measured in watts (W), which is a unit of energy per unit of time. It is a measure of the rate at which energy is being generated or expended.

2. What is the average power radiated by the human body?

The average power radiated by the human body is approximately 100 watts. This includes both the energy generated by the body's metabolic processes and the heat lost through radiation and convection.

3. How does the power radiated by the human body change with physical activity?

The power radiated by the human body increases with physical activity, as more energy is being generated and expended. However, the exact amount can vary depending on factors such as intensity and duration of the activity, as well as individual differences in metabolism.

4. Can the power radiated by the human body be measured externally?

Yes, the power radiated by the human body can be measured externally using devices such as calorimeters or infrared cameras. These methods can provide an estimate of the heat loss from the body, which can then be converted into power using the body's surface area and temperature difference.

5. How does the power radiated by the human body compare to other sources of radiation?

The power radiated by the human body is relatively low compared to other sources of radiation, such as the sun or electronic devices. For example, the average power radiated by the sun is approximately 3.8 x 10^26 watts, while a typical smartphone may emit around 3 watts of power.

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