Question 958: Thermodynamics & KTG

Question

A system is taken from state a to state c by two paths adc and abc as shown in the figure. The internal energy at a is ${U_a} = 10\,J$. Along the path adc the amount of heat absorbed dQ
1
$=$ 50 J and the work obtained dW
1
$=$ 20 J whereas along the path abc the heat absorbed dQ
2
= 36 J. The amount of work allong the path abc is
![](https://neetcare-image.cdn.examgoal.net/1qpq2yck7l6xnq8/0f01234d-b5e6-403b-823e-95a2354d288c/ec69e600-626a-11ea-bddc-5f310cab17d0/file-1qpq2yck7l6xnq9-342w.jpg)

Accepted Answer

From first law of thermodynamics
${Q_{adc}} = \Delta {U_{adc}} + {W_{adc}}$
$50\,J = \Delta {U_{adc}} + 20J$
$\Delta {U_{adc}} = 30J$
Again
${Q_{abc}} = \Delta {U_{abc}} + {W_{abc}}$
${W_{abc}} = {Q_{abc}} - \Delta {U_{abc}}$
${W_{abc}} = 36\,J - 30\,J$
${W_{abc}} = 6\,J$

Answer

10 J

Answer

12 J

Answer

36 J

Answer

6 J

Thermodynamics & KTG

Choose the correct answer: