Hot coffee is getting cooled, and temperatures shown are at t=0 sec. Heat transfer surface area...

  

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Hot coffee is getting cooled, and temperatures shown are at t=0 sec. Heat transfer surface area is 0.01m. Heat capacity of the coffee (mug and liquid coffee) is 50 Joules/ C. If the heat transfer coefficient is 200 Watts/(m. C). (Note: 1 Watt = 1 Joule/sec) Since the heat transfer rate is dependent on the temperature difference, take an average of the initial and final heat transfer rates to solve this problem. Find the time needed in seconds to cool the coffee to 50C. O s Hot coffee 70C Cool environment 20C Heat Hot coffee is getting cooled, and temperatures shown are at t=0 sec. Heat transfer surface area is 0.01m. Heat capacity of the coffee (mug and liquid coffee) is 50 Joules/ C. If the heat transfer coefficient is 200 Watts/(m. C). (Note: 1 Watt = 1 Joule/sec) Since the heat transfer rate is dependent on the temperature difference, take an average of the initial and final heat transfer rates to solve this problem. Find the time needed in seconds to cool the coffee to 50C. O s Hot coffee 70C Cool environment 20C Heat