Steel Balls at 150°C with a Specific Heat of 0

Multiple Choice

Steel balls at 150°C with a specific heat of 0.50 kJ/kg.°C are quenched in an oil bath to an average temperature of 70°C at a rate of 15 balls per minute. If the average mass of steel balls is 1.2 kg, the rate of heat transfer from the balls to oil is

A) 22.5 kJ/s
B) 12 kJ/s
C) 48 kJ/s
D) 10.5 kJ/s
E) 2880 kJ/s