Question

A system undergoes a process consisting of the following two steps

Step 1:the system absorbs 73 J of heat while 35 J of work done is done on it.

Step 2: the system absorbs 35 of j heat while performing 72 J of work

Calculate the change in internal energy for the overall process?

Answer 1

Step 1

$\Delta\>u=q+w$

$=73+35=108$

Step 2

$\Delta\>u=35-72=-37$

Overall change $=108-37$

$=71J$