Warm-Up Exercise 11

Due 10:00 am, Mon, Jan. 30

Physics 123, Winter Semester, 2012

Enter your 3-digit class identification number:

Enter the last 4 digits of your BYU ID:

Did you carefully complete the reading assignment?
yes no

Why would you want to use a heat pump (instead of an electric heater) to heat your house when 100% of the energy in an electric heater can be converted directly to heat? Isn't that more efficient? Explain.

The concept of reversibility and irreversibility is an important one. Carefully re-read section 22.3. If you still have questions, ask them below.
I did.
I didn't.

The Carnot engine is completely impractical---because it has to operate reversibly, it would take it an infinite time to complete a cycle. (Even operating *almost* reversibly, it will take a long time to complete a cycle---it would still be impractical.) Why then do we bother? What is important about this engine?

Why doesn't the Carnot engine have perfect efficiency?

Review: What's the difference between a reversible and an irreversible process?

Was there anything that you didn't understand in the reading assignment? If so, explain.

Comments:

Click here to submit answers:

Click here to erase all values: