Question

how many kilojoules of energy are necessary to raise the temperature of 3 kilograms of cast iron from 30 degrees Celsius to 120 degrees Celsius?

Answer 1

Specific heat of cast iron is 0.46 kJ / kg K.

Energy change = 0.46 kJ / kg K * 3 kg * (120 - 30) K = 124.2 kJ