Elasticity, Thermal Expansion, Calorimetry and Heat Transfer: Water Equivalent MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Practice and revisionDetailed answer reviewMobile-friendly flow

Water EquivalentHardQuestion 30854

Question

A 100 g calorimeter (c = 420 J/kg·K) contains 200 g water at 25°C. A hot metal sample (50 g, 100°C) is added and the final temperature is 29°C. The metal's specific heat is approximately:

A
994 J/kg·K
Correct
B
400 J/kg·K
C
500 J/kg·K
D
600 J/kg·K

Correct answer

994 J/kg·K

Explanation

The calorimeter and water gain $(0.1×420+0.2×4200)×4=3528$ J. The metal loses $0.05c(100-29)=3.55c$ J, so $c=3528/3.55≈<strong>994\text{ J/kg·K}</strong>$ .

Review Elasticity, Thermal Expansion, Calorimetry and Heat Transfer notes Start timed chapter practice