thick layer of insulation with a kinsul-0.03 W/m-°C. The convection heat transfer coefficients
on the inner and outer surfaces of the heater are 50 and 12 W/m²-°C, respectively. Determine
the cost of electricity required per year to maintain a water temperature of 55°C if the
surrounding air temperature is at 27°C. Assume a cost of electricity of 0.12 $/kW-hr.
Neglect radiation heat transfer and the thermal resistance of the tank. Assume the flow of
water to be zero. Also neglect the heat transfer from the top and bottom of the tank.
Fig: 1