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  • Airconditioning anomaly

    Saugata

    Member

    Updated: Oct 25, 2024
    Views: 1.1K
    An air-conditioned classroom is maintained at 72◦F in the summer. The
    students attend classes in shorts, sandals, and tee shirts and are quite comfortable.
    In the same classroom during the winter, the same students wear wool slacks, longsleeve
    shirts, and sweaters, and are equally comfortable with the room temperature
    maintained at 75◦F. Assuming that humidity is not a factor, please explain this apparent
    anomaly in “temperature comfort.”
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    Replies
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Replies

  • rahul69

    Member • Nov 18, 2012

    I think the reason is simple. As per my observation, human sense of temperature is relative in terms of hot and cold, So when a person enters a cold place wearing warm clothing, he will feel it even more colder and hence the warm clothing feels comfortable😁.
    Also the temperature which u mentioned (which is a little below room temperature), does not make any significant effect on human body. I guess if u sit in woolen dress in summer in this temperature u will be comfortable (of course only if u can be impartial in your mind about season)😉.
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  • Kaustubh Katdare

    Administrator • Nov 18, 2012

    Interesting observation and question here. From what I guess - the body gets used to a temperature and tries to find its own comfort level. So throughout the year, the students have 'adopted' to the small temperature variation in the classroom.
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  • Saugata

    Member • Nov 19, 2012

    I appreciate all your logic about the anomaly but I would be pleased to receive a more technical answer.
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  • zaveri

    Member • Nov 22, 2012

    The temperature for human comfort is exactly 25◦C.

    The function of an air-conditioner is to maintain this comfort temperature, and not to heat or cool as the laymen may think.


    so during summer, when the ambient temperature is quite high, the a/c reduces it to the psychrometric temperature.

    and again during winter, when the ambient temperature drops down, the machine increases it to the psychrometric temperature.
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  • kartik ns

    Member • Jan 13, 2013

    the process of heat transfer takes place only when there is a temperature difference. let us assume that the body temperature is '98.6 degrees.if the surrounding temperature is 72 degrees then the heat transfer takes place from the body to the surroundings. the temperature is the mean of the two values.
    now in winters, the body temperature rises because the woolen clothes absorb energy. the cold air causes heat to flow quickly and your body temperature will drop. However, if the temperature outside was 98.6 degrees, no heat would flow and your body temperature would rise because of the heat you generate.We need to be surrounded by air that is cooler than our body temperature by just the right amount so that heat flows away from our bodies at the same rate we generate it.
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