Q. A bubble of 8 mole of helium is submerged at a certain depth in water. The temperature of water increases by $30℃$. How much heat is added approximately to helium during expansion?
A) 4000 J
B) 3000 J
C) 3500 J
D) 4500 J
Explanation
(b) Heat added to helium during expansion
$H = nC_{V}\mathrm{\Delta}T = 8 \times \frac{3}{2}R \times 30\ \ \left( C_{V}\ for\ monoatomic\ gas = \frac{3}{2}R \right)$
=$360\ R$
= $360 \times 8.31\ J$ ($R$=$8.31\ J\ mol^{- 1} - K^{- 1})$
$\approx$ 3000 J
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.