
A Carnot engine uses a high temperature reservoir with temperature 800 K and efficiency 40%. In order to increase the efficiency to 50%, the temperature of the high reservoir must be increased to
T_{1} = 800 K
= 40%
= 50%
T_{1}= ?
Answer :

Efficiency of Carnot engine that operated with high temperature 400 K is 40 %, if the high temperature increase to 640 K. Calculate the efficiency!
= 40%
T_{1} = 400 K
T_{1} = 640 K
= ?
Answer :

Look at to a gas PV graphic below :
The ideal gas during AB process. Gas work during AB process is

Much work is done 1mol of gas if the gas isotermic expansion of 2 liters volume at pressures up 20.10^{5 }Nm^{2 }to 20 liters (the gas temperature 27^{0}C) is

On the graph below calculate the work done by machine!
Q_{1}= 2100 J
T_{1} = 700K
T_{2} = 400 K
W =.?
Answer :

An ideal refrigerator using 275 watts of electrical power and be able to remove the heat out of the machine at a rate of 850 joules per second. If the temperature inside the refrigerator 37^{0}C, determine the temperature outside the refrigerator!
W = 275 Watt
Q_{1 }= 850 Joule
T_{2 }= 37^{0}C = 310^{0}K
T_{1} = .?
Answer :

A Carnot engine uses a high temperature reservoir with temperature 300 K have efficiency 40%. If the high temperature reservoir have temperature 360 K, the efficiency become.
Answer :

Gases with internal energy 60 J absorb a heat 90 J from environment. If in the same time, system get work 150 J. Determine the internal energy at last!
U_{1} = 60 J
Q = 90 J
W = 150 J
U_{2} = ?
Answer :
U = Q W
U_{2} U_{1} = Q W
U_{2} 60 = 90 (150)
U_{2} = 240 + 60
U_{2} = 300 J

If R = 8,31 J/mol.K, so heat capacity of 4 mol nitrogen gases in constant pressure and low temperature is.

Heat capacity of 5 mol monoatomic gases in constant volume is.(R = 8,31 J/mol.K)