**Question: 4**

**Calculate the amount of heat energy required to raise the temperature of 100 g of copper from 20 ^{o}C to 70^{o}C. Specific heat capacity of copper =390 J kg-1 K-1.**

**Solution:**

Given

Mass of copper m = 100 g = 0.1 kg

Change of temperature △t = (70 – 20)^{0} C = 50^{0} C = 50 K

Specific heat capacity of copper = 390 J kg-1 K-1

The amount of heat required to raise the temperature of 0.1 kg of copper is

Q = m × △t × c

Q = 0.1 × 50 × 390

Q = 1950 J