A gas contained in a cylinder fitted with a frictionless piston expands against a constant external pressure or 1 atm from a volume of 5 litres to a volume of 10 litres. In doing so it absorbs 400 J of thermal energy from its surroundings. Determine the change in internal energy of system.

A gas contained in a cylinder fitted with a frictionless piston expand

1.	A gas contained in a cylinder fitted with a frictionless piston expands against a constant external pressure or 1 atm from a volume of 5 litres to a volume of 10 litres. In doing so it absorbs 400 J of thermal energy from its surroundings. Determine the change in internal energy of system.
Answer» <html><body><p></p>Solution :Given <a href="https://interviewquestions.tuteehub.com/tag/data-25577" style="font-weight:bold;" target="_blank" title="Click to know more about DATA">DATA</a> q = 400 J, `V_(1) = 5L , V_(<a href="https://interviewquestions.tuteehub.com/tag/2-283658" style="font-weight:bold;" target="_blank" title="Click to know more about 2">2</a>) = <a href="https://interviewquestions.tuteehub.com/tag/10-261113" style="font-weight:bold;" target="_blank" title="Click to know more about 10">10</a> L`<br/>`Delta <a href="https://interviewquestions.tuteehub.com/tag/u-1435036" style="font-weight:bold;" target="_blank" title="Click to know more about U">U</a>` = q - <a href="https://interviewquestions.tuteehub.com/tag/w-729065" style="font-weight:bold;" target="_blank" title="Click to know more about W">W</a> (heat is given to the system (+q), work is done by the system (-w)<br/>`Delta u = q - Pd V `<br/>= 400 J - 1 atm ( 10 - 5) L<br/>= 400 J - 5 atm L[`:'`1 L atm = 101 . 33 J ]<br/>= 400 J - ` 5 xx 101 . 33 ` J<br/>= 400 J - 506 65 J<br/>= - 106 . 65 J .</body></html>