Velocity (linear)Kinematics
v = v₀ + a t
Displacement (linear)Kinematics
s = v₀ t + ½ a t²
Velocity-squaredKinematics
v² = v₀² + 2 a s
Uniform motionKinematics
x = x₀ + v t
Angular velocityKinematics
ω = ω₀ + α t
Angular displacementKinematics
θ = ω₀ t + ½ α t²
Angular velocity-squaredKinematics
ω² = ω₀² + 2 α θ
Centripetal accelerationKinematics
a_c = v² / r = ω² r
Newton's 2nd lawDynamics
F = m a
ImpulseDynamics
J = ∫ F dt = Δp
Work (line integral)Dynamics
W = ∫ F · ds
PowerDynamics
P = dW/dt = F · v
Kinetic energyDynamics
E_k = ½ m v²
Rotational KEDynamics
E_rot = ½ I ω²
Potential energy (near Earth)Dynamics
E_p = m g h
Rotational dynamicsDynamics
∑τ = I α
Force equilibriumStatics
∑F = 0
Moment equilibriumStatics
∑M = 0
Friction limitStatics
F_f ≤ μ N
Ideal gas (molar)Thermodynamics
p V = n R T
Ideal gas (specific)Thermodynamics
p v = R T
First law (closed)Thermodynamics
ΔU = Q − W
Internal energyThermodynamics
U = m c_v T
EnthalpyThermodynamics
h = u + p v
Enthalpy (cp)Thermodynamics
H = m c_p T
Specific heatsThermodynamics
c_p − c_v = R
Adiabatic relationThermodynamics
p v^γ = const
Isentropic T ratioThermodynamics
T₂/T₁ = (p₂/p₁)^{(γ−1)/γ}
Isentropic density ratioThermodynamics
ρ₂/ρ₁ = (p₂/p₁)^{1/γ}
Continuity (incompressible)Fluids & Aero
A₁ V₁ = A₂ V₂
BernoulliFluids & Aero
p + ½ ρ v² + ρ g h = const
Dynamic pressureFluids & Aero
q = ½ ρ v²
Reynolds numberFluids & Aero
Re = ρ v L / μ
Speed of soundFluids & Aero
a = √(γ R T)
Mach numberFluids & Aero
M = v / a
Lift forceFluids & Aero
L = ½ ρ v² C_L A
Drag forceFluids & Aero
D = ½ ρ v² C_D A
Skin friction (turbulent plate)Fluids & Aero
C_f ≈ 0.026 Re^{−1/7}
Stagnation pressureFluids & Aero
p₀/p = (1 + (γ−1) M² / 2)^{γ/(γ−1)}
Stagnation temperatureFluids & Aero
T₀/T = 1 + (γ−1) M² / 2
Isentropic densityFluids & Aero
ρ₀/ρ = (1 + (γ−1) M² / 2)^{1/(γ−1)}
Vis-vivaOrbital Mechanics
v² = μ (2/r − 1/a)
Circular orbit speedOrbital Mechanics
v_c = √(μ / r)
Escape speedOrbital Mechanics
v_e = √(2 μ / r)
Orbital periodOrbital Mechanics
T = 2 π √(a³ / μ)
Specific energyOrbital Mechanics
ε = − μ/(2 a)
Specific ang. momentumOrbital Mechanics
h = √(μ a (1 − e²))
Periapsis radiusOrbital Mechanics
r_p = a (1 − e)
Apoapsis radiusOrbital Mechanics
r_a = a (1 + e)
Hohmann Δv₁Orbital Mechanics
Δv₁ = √(μ/r₁) (√(2 r₂/(r₁+r₂)) − 1)
Hohmann Δv₂Orbital Mechanics
Δv₂ = √(μ/r₂) (1 − √(2 r₁/(r₁+r₂)))
Plane changeOrbital Mechanics
Δv = 2 v sin(Δi/2)
Mean motionOrbital Mechanics
n = √(μ / a³)
DensityAtmosphere
ρ = p / (R T)
ISA lapse (troposphere)Atmosphere
T = T₀ − L h
Pressure vs altitudeAtmosphere
p = p₀ (T/T₀)^{g₀/(R L)}
Gravity vs altitudeAtmosphere
g(h) ≈ g₀ (R_E/(R_E+h))²
Scale heightAtmosphere
H = R T / (M g)
Geopotential heightAtmosphere
H_g = (R_E h)/(R_E + h)