Question

When heat energy of $1500$ $J$ is supplied to a gas at constant pressure of $2.1\times {10}^{5}N/m^2$ then there is an increase in its volume up to $2.5\times {10}^{-3}{m}^3$. The increase in internal energy of the gas (in joule) is :

• A. $450J$
• B. $525J$
• C. $975J$
• D. $2025J$

Answer 1

Answer: (C)

$975J$

Change in internal energy $=$ Heat energy added $+$ work done

$\Delta U=1500-(2.1\times {10}^5)\times (2.5\times {10}^{-3})$

$\Delta U=1500-525=975J$