Show that the internal energy of the air (treated as an ideal gas) contained in a room remains constant as the temperature changes between day and gight. Assume that the atmospheric pressure around remains constant and the air in the room maintains this prssure by communicating with the surrounding thourgh the widows, doors, etc.

Explanation

Internal energy = nRT
` Now, PV = nRT`
` nT = PV`
` here P and V constant So, nT is constant`
` :. Internal energy = R xx constant `
` = constant `.