Mass = 100g = 0.1kg
Specific heat = 4.8 J/(kg x c)
del T = (100-30) degree celcius = 70 degrees celcius
Heat Loss = mass x specific heat x del T
= (0.1 x 4.8 x 70) J
= 33.6 J
So, the loss of heat when 100 g of iron is cooled down from Temperature of 100 degrees celcius to a Temperature of 30 degrees celcius is 33.6 J.
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