JEE Main On 8 April 2017 Question 13

Question: In an experiment a sphere of aluminium of mass 0.20 kg is heated upto $ 150^{o}C $ . Immediately, it is put into water of volume $ 150cc $ at $ 27^{o}C $ kept in a calorimeter of water equivalent to 0.025 kg. Final temperature of the system is $ 40^{o}C $ . The specific heat of aluminium is - (take 4.2 Joule = 1 calorie) [JEE Online 08-04-2017]

Options:

A) $ 434J/k{g^{-o}}C $

B) $ 378J/k{g^{-o}}C $

C) $ 315J/k{g^{-o}}C $

D) $ 476J/k{g^{-o}}C $

Show Answer

Answer:

Correct Answer: A

Solution:

  • Q given = Q used $ 0.2\times S\times (150-40)=150\times 1\times (40-27) $ $ +25\times (40-27) $ $ 0.2\times S\times 110=150\times 13+25\times 13 $ $ S=\frac{13\times 25\times 7}{0.2\times 110} $ $ S=434 $