Px154 Revision Flashcards
(33 cards)
What does isobaric mean and it’s associated equation?
At a constant pressure, W = pdV
What does isothermal mean and what are it’s associated equations?
At a constant temperature, P1V1 = P2V2, W = Q = nRT integral(dV/V)
What does adiabatic mean and what are the associated equations?
No transfer of heat, P1V1^gamma = P2V2^gamma, T1V1^(1-gamma) = T2V2^(1-gamma)
What does isochoric mean and it’s associated equations?
At a constant volume, W = 0, Q = delta U = nCv deltaT
What is the formula for gamma in thermodynamics?
CP/Cv
How do you tell the difference between an adiabatic process and an isothermal process on a PV diagram?
An adiabatic process will always have a greater pressure drop
At room temperature for a monatomic gas, what is gamma?
5/3
At room temperature for a diatomic gas, what is gamma?
7/5
What is the volume expansion coefficient given the linear expansion coefficient alpha?
3xalpha
What is the wave speed formula?
V = w/k
What is the wave equation?
d^2U/dT^2 = V^2 d^2U/dX^2
How is V related to tension in a string?
V = √(T/mu)
What is the work done by an isobar?
P deltaV
What is the entropy formula?
Integral(1/T dQ)
What are the units of entropy?
JK^-1
What is the first law of thermodynamics and it’s formula and differential form?
Energy cannot be created or destroyed, only transferred between stores.
Delta U = Q - W
dU = dQ - pdV
What is Cv and it’s related equation?
The heat capacity at a constant volume
Cv = 1/n dQ/dT or 1/n dU/dT
At room temperature, what is Cv for a monatomic and diatomic gas?
3R/2, 5R/2
At room temperature, what is Cp for a monatomic and diatomic gas?
5R/2, 7R/2
What is the coefficient of performance for a carnot engine heating and coolong a room?
|Qh|/W, |Qc|/W
What is the formula for the phase speed?
w/k
What is the formula for the group velocity?
dw/dk
What are w and k in a wave equation?
w is the t coefficient, k is the x coefficient
What is malus’ law?
I = I0 cos^2 (∅)