Question

When heat energy of 2000 joules is supplied to a gas at constant pressure 2.1 x 10⁵ N/m², there is an increase in its volume equal to 2.5 x 10^-3 m³. The increase in internal energy of the gas in joules is ____________.

Options

• 450

• 525

• 1475

• 2025

Answer 1

When heat energy of 2000 joules is supplied to a gas at constant pressure 2.1 x 10⁵ N/m², there is an increase in its volume equal to 2.5 x 10^-3 m³. The increase in internal energy of the gas in joules is 1475.

Explanation:

By 1^st law of thermodynamics,

`"Q" = Delta"U" + "P"(Delta"V")`

`therefore Delta"U" = "Q" - "P"(Delta"V")`

`= 1500 - (2.1 xx 10^5) (2.5 xx 10^3)`

` = 1475  "J"`