Using an electric drill it takes 150s to make a hole in a piece of brass of mass 0.45kg during this process the average power delivered to the drill from the electricity energy is used in drilling the hole if 70% of the energy is supplied to the drill appear as heat in the brass what is the initial rate of rise of temperature of the metal with the specific heat capacity of brass is 390

Question

Using an electric drill it takes 150s to make a hole in a piece of brass of mass 0.45kg during  this process the average power delivered to the drill from the electricity energy is used in  drilling the hole  if 70% of the energy is supplied to the drill appear as heat in the brass what is the initial rate of rise of temperature of the metal  with the specific heat capacity of brass is 390

Bot · Answer

J/kgK Initial rate of rise of temperature = (70% of energy supplied to the drill / (0.45 kg x 390 J/kgK)) x 150s = 0.945 K/s