ChatGPT:
Option 1 — Add the cold milk immediately — will result in a lower final temperature after 2 minutes.
Why: • Heat loss depends on the temperature difference between the coffee and the environment (usually room temperature). • If you add the milk early, the overall temperature of the coffee-milk mixture is reduced immediately. This lowers the average temperature over the 2 minutes, so less heat is lost to the air. • If you wait 2 minutes to add the milk, the hotter coffee loses more heat to the environment during those 2 minutes, but when you finally add the milk, it doesn’t cool it as much because the coffee’s already cooler and the temp difference between the milk and the coffee is smaller.
Summary: • Adding milk early = cooler overall drink after 2 minutes. • Adding milk late = higher overall temp after 2 minutes, because more heat escapes during the time the coffee is hotter.
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