Answer: emitter.
- A emitter
- B reflector
- C insulator
- D transmitter
Correct answer: A. emitter
Explanation: By Kirchhoff’s law, a good absorber is an equally good emitter at the same temperature.
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.