Answer: The temperature difference between body and surroundings is small.
- A The temperature difference between body and surroundings is large
- B The temperature difference between body and surroundings is small
- C The body is a perfect black body
- D The surrounding temperature is 0 K
Correct answer: B. The temperature difference between body and surroundings is small
Explanation: Newtons law of cooling is an approximation valid only for small temperature differences between the body and its surroundings.
During a phase change (melting or boiling), temperature stays constant while heat is absorbed entirely as latent heat (Q=mL); temperature only rises again once the substance is fully in its new phase.
Concept context
Temperature scales, thermal expansion, calorimetry, and the three modes of heat transfer including radiation laws.