2nd Law of Thermodynamics

Question 1

2nd Law of Thermodynamics

Answer 1

• Heat does not spontaneously flow from cold to hot
• No engine is 100% efficient

Question 2

Heat Engine I/O Equation

Answer 2

• W = Qh - Qc
• W is work done (output)
• Qh is heat absorbed by engine (input)
• Qc is the heat rejected by engine (wasted output)

Question 3

Efficiency of Heat Engine

Answer 3

ϵ = W/Qh

Question 4

Fridge Engine I/O Equation

Answer 4

Qh = W + Qc

Question 5

Efficiency of Fridge

Answer 5

K = Qc/W

Question 6

Order of processes for Carnot Cycle

Answer 6

• Isothermal
• Adiabatic
• Isothermal
• Adiabatic

Question 7

Efficiency of Carnot Cycle

Answer 7

E = 1 - (Tc/Th)

Question 8

Total work done for a carnot cycle

Answer 8

W=Q=nRΔT ln(V2/V1)

Question 9

Change in entropy equation

Answer 9

• ΔS = Q/T
• ∫ dQ/T