2. A cup of tea is prepared in a preheated cup with hot water so that the temperature of both the cup and the brewing tea is initially 200° F. The cup is then left to cool in a room kept at a constant 60° F. Three minutes later, the temperature of the tea is 140° F. Determine (a) the temperature of the tea after 6 minutes and (b) the time required for the tea to reach 80° F.

2. A cup of tea is prepared in a preheated cup with hot water so that the temperature of both the cup and the brewing tea is initially 200° F. The cup is then left to cool in a room kept at a constant 60° F. Three minutes later, the temperature of the tea is 140° F. Determine (a) the temperature of the tea after 6 minutes and (b) the time required for the tea to reach 80° F.

Solid Waste Engineering

3rd Edition

ISBN:9781305635203

Author:Worrell, William A.

Publisher:Worrell, William A.

Chapter7: Thermal Processes

Section: Chapter Questions

Problem 7.4P

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