THE PRACTICE STUDIO
Go slowly. Ask why. Make it yours.
PRACTICE / Newton’s law of cooling
Halve the excess twice
An object cools in a room at 20°C. Its temperature falls from 80°C to 50°C in 6 minutes and obeys Newton’s cooling law with constant coefficient.
How long after the initial 80°C reading does it reach 35°C?
Organize the givens & assumptions
- Room temperature: 20°C
- Initial temperature: 80°C
- Temperature after 6 min: 50°C
- Target temperature: 35°C
Constant ambient temperature and cooling coefficient; lumped uniform object temperature over this range.
- A
- B
- C
- D
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