Physics - Heat & Thermo Question with Solution | TestHub

A metal vessel of negligible heat capacity contains $0.5\mathrm{kg}$ of water (of specific heat capacity $4200\mathrm{J}$ $\mathrm{k}{\mathrm{g}}^{-1}{\mathrm{K}}^{-1}$). It is heated from $15{}^{\circ }\mathrm{C}$ to $85{}^{\circ }\mathrm{C}$ by $750\mathrm{W}$ immersion heater in 4 minutes. The average loss of heat in watts to the surroundings from the vessel during this time is nearly :