# 21

# Homework

## Question 1

A cooling system is being used in order to decrease heat gradually from a house at a rate of 900 kJ/min while drawing electric power at a rate of 75 kW. Determine the COP of this system and the rate of heat transfer to the outside weather.

**Given:**

**Find:**

Determine the COP of this system and the rate of heat transfer for the outside weather.

## Question 2

Through the isothermal heat addition process of Carnot cycle, amount of hear, 750 kJ, was added to a fluid from a source at C. Determine the entropy change of the working fluid, the entropy change of the source, and the total entropy change for the process.

**Given:**

**Find:**

Determine the entropy change of the working fluid, the entropy change of the source, and the total entropy change for the process.