JEE Main 2019 Physics question
A metal ball of mass 0.1 kg is heated up to 500°C and dropped into a vessel of heat capacity 800 JK and containing 0.5 kg water. The initial temperature of water and vessel is 30°C. What is the approximate percentage increment in the temperature of the water? [Specific Heat Capacities of water and metal are, respectively, 4200 JkgK and 400 JkgK]
Answer: (A)
Solution
40(500 − T) = 2900(T − 30) ⇒ T ≈ 36.4°C: increase ≈ 21% of 30°C.