Sheet
Formulae
The compact kit. Every identity in the academy, grouped the way a first-year engineering exam is grouped. Print it in your head.
I. Kinematics
Velocityv = dx/dt
m/s
Accelerationa = dv/dt
m/s²
Constant av = v₀ + at
—
DisplacementΔx = v₀t + ½at²
—
Timelessv² = v₀² + 2aΔx
—
RangeR = v₀² sin(2θ)/g
level ground
II. Forces
Second lawΣF = ma
N = kg·m/s²
WeightW = mg
g ≈ 9.81 m/s²
Kinetic frictionf_k = μk N
opposes slip
Angle of reposeθc = arctan μs
—
Ramp accelerationa = g(sinθ − μk cosθ)
down the plane
III. Energy
WorkW = F Δr cosα
J
PowerP = F · v
W = J/s
Kinetic energyKE = ½mv²
J
Gravitational PEPE = mgh
datum-dependent
Spring PEPE = ½kx²
J
IV. Momentum & rotation
Momentump = mv
kg·m/s
ImpulseJ = Δp = F_avg Δt
N·s
Restitutione = (v₂ − v₁)/(u₁ − u₂)
0…1
Torqueτ = r F sinθ
N·m
Rotationτ = Iα
I in kg·m²
V. Oscillation & waves
SHMω = √(k/m)
rad/s
PendulumT = 2π√(L/g)
small angle
Wave identityv = fλ
—
String speedv = √(T/μ)
μ = kg/m
String harmonicsf_n = nv/(2L)
fixed-fixed
VI. Applied physics
HydrostaticP = P₀ + ρgh
Pa
BuoyancyF_b = ρ V g
N
BernoulliP + ρgh + ½ρv² = const
streamline
ContinuityA₁v₁ = A₂v₂
incompressible
Carnotη = 1 − T_C/T_H
kelvin
OhmV = IR
V, A, Ω
Electrical powerP = IV = I²R
W