Question

Thirty joules of heat flow into the system. The system in turn does 50 joules of work .The internal energy of the system has
a)increased by 20 joules
b)decreased by 80 joules
c)decreased by 20 joules
d)increased by 80 joules ​

Answer 1

Answer:Increased by 20 J.

Output work-input work

=+20 J

which is positive therefore increased.

Explanation:

Answer 2

$\huge\mathfrak\pink{\underline{\underline{AnSwer}}}$

★ Apply 1st LAw of Thermodynamics ★

∆E = q + w

here,

∆E = 30J - 50J

∆E = -20J

i.e Internal energy decreased by 20 joules

● Your answer is option 3 ●

Happy to help!

:)