Problems Solving on Entropy 1

TL;DR

This video discusses a problem on entropy, where a reversible engine operates between three heat reservoirs and calculates the quantity of heat supplied by each reservoir.

Transcript

hello friends so in this video i am going to solve a problem on entropy in this problem a reversible engine will operate between three heat reservoirs which are 1000 kelvin 800 kelvin and 600 kelvin and rejects heat to a reservoir that is at 300 kelvin the engine develops 10 kilowatt and rejects 412 kilojoules per minute of heat if heat supplied by... Read More

Key Insights

• 🥵 A reversible engine operates between multiple heat reservoirs and follows the principles of energy and entropy balance.
• 🥵 The quantity of heat supplied by each reservoir can be determined by solving simultaneous equations.
• 👻 The given conditions and equations allow the conversion of values between different units, such as kilojoules per minute to kilowatts.
• 🥵 Energy balance equations help in calculating the heat supplied and rejected by the engine, as well as the work output.

Questions & Answers

Q: What is the problem discussed in this video?

The problem focuses on determining the quantity of heat supplied by each heat reservoir in a reversible engine operating between three reservoirs and rejecting heat to a reservoir at a lower temperature.

Q: What are the temperatures of the three heat reservoirs involved?

The temperatures are 1000K, 800K, and 600K for the heat reservoirs supplying heat to the engine.

Q: How much power does the engine develop?

The engine develops 10kW of power.

Q: How much heat is rejected by the engine per minute?

The engine rejects 412 kJ/min of heat to the reservoir at 300K.

Q: What is the relationship between the heat supplied by the 1000K and 600K reservoirs?

The heat supplied by the 1000K reservoir is 60% of the heat supplied by the 600K reservoir.

Q: How is the value of q4 converted to kilowatts?

The value of q4, given in kilojoules per minute, is converted to kilowatts by dividing it by 60, resulting in 6.866 kW.

Q: What is the equation used for energy balance?

The equation for energy balance is: q1 + q2 + q3 = q4 + w, where q1, q2, and q3 are heat supplied by the reservoirs, q4 is the rejected heat, and w is the work output.

Q: What is the value of q1 obtained in the calculation?

The value of q1 is calculated to be 4.05 kW.

Summary & Key Takeaways

• A reversible engine operates between three heat reservoirs at temperatures of 1000K, 800K, and 600K, and rejects heat to a reservoir at 300K. The engine develops 10kW of power and rejects 412 kJ/min of heat.

• Given that the heat supplied by the reservoir at 1000K is 60% of the heat supplied by the reservoir at 600K, the problem is to determine the quantity of heat supplied by each reservoir.

• By applying energy balance and entropy balance equations, the values of q1, q2, and q3 are calculated to be 4.05kW, 6.066kW, and 6.75kW respectively.