Write an expression for the efficiency of a Carnot engine.
Asked by Topperlearning User
| 4th Jun, 2014,
01:23: PM
Expert Answer:
Where W is the work done by the engine per cycle. Q1 is heat extracted from the source, Q2 is heat given to the sink. T1 is the temperature of the source and T2 is the temperature of the sink. is always expressed as a percentage.
Answered by
| 4th Jun, 2014,
03:23: PM
Concept Videos
- State second law of thermodynamics. Distinguish between heat engine and refrigerator
- State the second law of thermodynamics in terms of entropy.
- How does the Second Law of Thermodynamics help in the working of a refrigerator?
- State a few statements for second law of thermodynamics.
- State two conditions of a reversible process. What is a quasi-static process?
- Answer the following questions : (i) A piece of iron is hammered. Does the internal energy of the iron increase? Does the heat enter the piece of the iron from outside? (ii) A hot piece of lead is immersed in cold water. Has the internal energy of the water increased? Has any work been done by the lead? (iii) Why are the brake-drums of a car heated when the car moves down a hill at constant speed? (iv) Two balls of the same metal having masses 10g and 20g collide with a target with the same velocity. If the total energy is used in heating the balls, which ball will attain higher temperature? (v) An ideal gas is compressed at a constant temperature. Will its internal energy increase or decrease? (vi) How can the internal energy of an ideal gas be changed?
- A Carnot's engine, whose sink is at a temperature of 300K, has an efficiency of 40%. By how much should the temperature of the source be increased so as to increase the efficiency to 60%?
- State whether the following processes are reversible or irreversible : (i) Heat production by friction (ii) The growth of a planet (iii) Diffusion of gases (iv) Electrolysis (v) Sudden unbalanced expansion of a gas (vi) Carnot's cycle (vii) Joule's heating in an electrical resistance.
- The P - V diagram for a cyclic process is a triangle ABC drawn in order. The co-ordinates of A, B, C are (4,1), (2,4), and (2,1). The co-ordinates are in the order (P-V). Pressure is in Nm-2 and volume is in litre. Calculate work done during the process from A to B, B to C, and C to A. Also, calculate work done in the complete cyclic.
Kindly Sign up for a personalised experience
- Ask Study Doubts
- Sample Papers
- Past Year Papers
- Textbook Solutions
Sign Up
Verify mobile number
Enter the OTP sent to your number
Change