Final answer:
To create a model for the coffee's temperature after t minutes using Newton's Law of Cooling, we use the given initial conditions and solve for the cooling constant k. Then we can express F(t) completely to predict future temperatures.
Step-by-step explanation:
To find the model for the temperature of the coffee, F(t), after t minutes using Newton's Law of Cooling, we need to use the formula F(t) = C + (To - C)eat, where:
- C is the constant temperature of the surrounding medium (68° F),
- To is the initial temperature of the object (170° F), and
- k is the cooling constant we need to find.
Given that after 30 minutes the temperature of the coffee is 90° F, we can substitute the values into the equation to find the value of k:
90 = 68 + (170 - 68)e30k
Solving for k, we find the cooling constant. Once we have k, we can write the complete model for the temperature of the coffee as a function of time, t, in minutes.