Mass of water (m1)=150 g=0.15 g
Mass of metal (m2)=0.20 kg
Water equivalent of calorimeter W=0.025 kg
t1=27∘C,t2=150∘C,t=40∘C,s1=4.2×103Jkg−1K−1
Heat gained by water and calorimeter =(m1+w)×s1×(t−t1)
=(0.15+0.025)×4.2×103×(40−27)=9.555×103J
Heat lost by metal =m2×s×(t2−t)=0.20×s×(150−40)=22 sJ, where s is the specific heat of metal,
Equating (1) and (2), we have
s=0.43×103Jkg−1K−1.