Question

A beaker contains 200 g of water. The heat capacity of beaker is equal to that 20 g of water. The initial temperature of water in the beaker is 20°C . If 440 g of hot water at 92°C is poured in, the final temperature, neglecting radiation loss, will be (a) 58°C (b) 68°C (c) 73°C (d) 78°C

Answer 1

Answer:

Let the final temperature of the system be T.

Thus the heat absorbed by the cold water and beaker system=200×1×(T−20)+20×1×(T−20)

Heat lost be the hot water=440×1×(92−T)

From conservation of heat energy,

200×1×(T−20)+20×1×(T−20) =440×1×(92−T)

⟹T=68  

∘

C

Explanation: