Thermal Physics Question

    • Thread Starter

    The question states;

    A student uses a microwave oven to warm up a cup of cold tea.

    Thermal energy is supplied to the tea at a rate of 750 W. The tea has a mass of 0.42 kg and an initial temperature of 17 degrees C. Calculate the final temperature of the tea. Assume the specific heat capacity of the tea is 4200 J kg-1 K-1.

    I understand how to calculate the final temperature, but first I have to change the 750 Watts into joules, however, the question gives no time which I can use for the equation Q = Power x time.

    Am I missing something obvious here, or has the question been printed incorrectly?


    Must be printed incorrectly, can't see any way around it

    Agree. Someone forgot to tell you how long the thing's being heated for.
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Updated: October 12, 2016
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