A cup of coffee at 86 degrees Celsius is placed in a room at 24 degrees Celsius.
ID: 3372524 • Letter: A
Question
A cup of coffee at 86 degrees Celsius is placed in a room at 24 degrees Celsius. Suppose that the coffee cools at a rate of 4 degrees Celsius per minute when the temperature of the coffee is 70 degrees. Let T(t) be the temperature of the coffee at time t.>style="font-family: arial, sans-serif; font-size: medium; background-color: rgb(232, 232, 232);">style="font-family: arial, sans-serif; font-size: medium; background-color: rgb(232, 232, 232);">
The differential equation describing this has the form dT/dt = k(T-A), where A = 24. Find k.
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k is not -4/62
A cup of coffee at 86 degrees Celsius is placed in a room at 24 degrees Celsius. Suppose that the coffee cools at a rate of 4 degrees Celsius per minute when the temperature of the coffee is 70 degrees. Let T(t) be the temperature of the coffee at time t. The differential equation describing this has the form dT/dt = k(T-A), where A = 24. Find k. k =Explanation / Answer
The answer is -4/(70-24)=-4/46=-2/23=-0.87...Note the rate of cooling is given at 70 C