Question

Work done by 50 cal. of heat in isothermal expansion of ideal gas is:

• A. 209.2 J
• B. 2.092 J
• C. 20.92 J
• D. None of the above

Answer 1

The correct option is A 209.2 J

We know that $1Calorie=4.184J$ therefore $50Calorie=50\times 4.184=209.2J$
$q=209.2J$
According to the first law of thermodynamics,
$△U=q+w$
since process is isothermal $△U=0$ so $q=-w$
so, $w=-209.2J$
hence magnitude of work done $=209.2J$