What is change in internal energy if 30j of heat are released from a system that does 50j of work on its surroundings

Question

asked Jan 14, 2020 102k views

2 Answers

Austio · Answer 1 · 2020-01-20T22:49:06+0000

Answer:

-80 J

Step-by-step explanation:

The first law of thermodynamics states that:

$\Delta U = Q - W$

where

$\Delta U$ is the change in internal energy of the system

Q is the heat absorbed by the system

W is the work done by the system

In this problem, we have:

Q = -30 J is the heat released by the system (negative because the system releases it)

W = +50 J is the work done by the system on the surrounding (positive since it is done by the system)

Therefore, the change in internal energy is

$\Delta U = -30 J - (+50 J) = -80 J$