An electric furnace is to melt 40 kg of aluminium/hour. the initial temperature of aluminium is 32°c. given that aluminium has specific heat capacity 950 j/kg k melting point 680*c, latent heat of fusion 450 kj/kg, the efficiency of furnace is 85% and cost of energy is 20 cents/kwhr calculate: (a) power required (b) the cost of operating the furnace for 30 hours

Part a)

P = 13.93 kW

Part b)

R = 8357.6 Cents

Explanation:

Part A)

heat required to melt the aluminium is given by

here we have

Since this is the amount of aluminium per hour

so power required to melt is given by

Since the efficiency is 85% so actual power required will be

Part B)

Total energy consumed by the furnace for 30 hours

now the total cost of energy consumption is given as