Answer: 1000 nm.
- A 1000 nm
- B 500 nm
- C 2000 nm
- D 250 nm
Correct answer: A. 1000 nm
Explanation: λ<sub>max</sub> = b/T = 2.9×10<sup>-3</sup>/2900 = 10<sup>-6</sup> m = 1000 nm.
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.