Thread: Newton's Law of cooling

can somebody help me solving the following problem..its related to newton's law of cooling..
the problem is:

Mr. Hassan and Mr, Mohsin both order coffee at the lunch counter and receive their cups at the same time. Mr. Hassan adds cream at once but does not take his coffee until 5 minutes later.Mr. mohsin waits for 5 minutes,then adds cream and begins to drink. Who takes the hotter coffee??..

plz respond

Originally Posted by AwaisAmin

can somebody help me solving the following problem..its related to newton's law of cooling..
the problem is:

Mr. Hassan and Mr, Mohsin both order coffee at the lunch counter and receive their cups at the same time. Mr. Hassan adds cream at once but does not take his coffee until 5 minutes later.Mr. mohsin waits for 5 minutes,then adds cream and begins to drink. Who takes the hotter coffee??..

plz respond

This question makes an assumption (probably incorrect from a thermodynamics point of view) that adding the cream reduces the temperature a fixed number of degrees.

the coffee with the cream added at t = 0 has its initial temperature reduced a fixed number of degrees, however, the coffee w/o the cream added at t = 0 will cool at a faster rate than the coffee with the cream added at t = 0 (why?)

after 5 minutes the cream is added to the second cup which reduces its temperature the fixed number of degrees.

so ... which will have the higher temperature at t = 5 after the cream is added to the second coffee?


in reality, the serious student would conduct a carefully designed and controlled experiment in the middle of the night, drinking the coffee samples to remain awake while analyzing the data. I look forward to your analysis and conclusion.