Thermodynamics Equations - AP Physics 2

Converting from celsius to kelvin

K = C + 273.15

The Ideal Gas Law (moles)

PV = nRT

The Ideal Gas Law (molecules)

PV = Nkt (k is Boltzmann’s Constant)

Standard temperature and pressure

273.15K, 1.00atm or 1.013 x 10⁵ N/m²

1 mole of gas at STP in liters

22.4L

Avogadro’s number

N_A = 6.02 x 10²³ molecules per mole

Boltzmann’s constant

k = 1.38 x 10^-23 J/K

Average KE of molecules in gas

KE = (3/2)kT or KE = (1/2)mv²

Internal energy in an ideal monatomic gas

U = (3/2)nRT

The rate of heat flow

(Q/t) = kA(T₁ – T₂)/l (I is a lowercase L, k is thermal conductivity)

Change in internal energy

ΔU = Q + W

Isothermal process

ΔU = 0, Q = -W

Adiabatic process

Q = 0, ΔU = W

Isobaric process

ΔU = Q - W

Isochoric process (isovolumetric)

W = 0, ΔU = Q