Hot Cereal


Ms. Jamison overheated her cereal
in the morning and needs to wait while it cools before she cant eat it.
If the cooling rate is known, she wonders how she might calculate the waiting time.
What is known:
 The cereal was heated to 90°C.
 After 1 minute, the cereal cooled to 60°C.
 the room temperature is 25°C.
 Ms. Jamison starts her breakfast when the cereal's temperature is
40°C.
 The temperature difference between the cereal and the room changes
with time according to the following equation
dθ/dt = kθ
where θ is the temperature difference
of the cereal and room; t is the time and k is the cooling constant.
