question_answer 49)

  Photons absorbed in matter are converted to heat. A source emitting n photon/sec of frequency v is used to convert 1 kg of ice at 0°C to water at 0°C. Then, the time T taken for the conversion (a) decreases with increasing n, with v fixed (b) decreases with n fixed, v increasing (c) remains constant with n and v changing such that  = constant (d) increases when the product  increases

Answer:

  Energy spent to convert ice into water Energy of photons used                                                                      or when V is constant ; when n fixed ; .Thus T is constant if is constant . thus option (a), (b) and (c) are correct.