AP Physics C Equations

Flashcards of key equations for AP Physics C Mechanics and E&M.

V2 = V0 2 + 2ax

Time-independent kinematics equation

∑F = ma

Net force (Newton’s second law)

F = dp/dt

Force in terms of momentum (Newton’s 2nd law as a derivative)

F = - dU/dx

Force in terms of Potential Energy

J = ∫Fdt

Impulse

p = mV

Definition of momentum

J = Δp

Impulse - Momentum Theorem

FF≤μFN

Force of friction

W = F * d

Work done by a constant Force (dot product)

W = ∫F * ds

Work done by a variable force (integral)

EK = 1/2 mv2

Kinetic energy (linear)

WNet = ΔEk

Work – Energy Theorem

P = dW/dt

Power (as a rate of change)

P = F * v

Power – alternate expression (dot product)

ac = V2/r = ω2r

Centripetal acceleration

τ = r × F

Torque (defined as a cross product)

∑τ = Iα

Newton’s second law for rotation (torque and angular acceleration)

I = ∑miri2

Moment of inertia of a collection of particles (no integral)

IParallel = ICOM + mh2

Parallel Axis Theorem

IRod = ml2/12

Rotational inertia of a rod about an axis through its center

l = r×p

Angular Momentum of a moving particle (cross product)

L = Iω

Angular Momentum of a rigid rotation body (in terms of the rotational inertia)

rcom = ∑miri/M

Position of center of mass for a collection of particles (sigma notation)

ω×r = V→V = rω

Conversion between linear and angular velocity (No slip)

EK = 1/2 Iω2

Rotational kinetic energy

F = - kx

Force of a spring (Hooke’s Law)

USpring = 1/2 kx2

Potential energy of a spring

T = 2π√(m/k)

Period of a Spring Mass System

ω = √(MgD/I)

Angular frequency of general pendulum

T = 2π√(l/g)

Period of a simple pendulum

1/T = f = ω/2π

Relationships between period, frequency and angular frequency

FG = G m1m2/r2

Newton’s law of Gravitation

UG = - G m1m2/r

Gravitational Potential Energy

UTotal = - G m1m2/2r

Total Mechanical Energy of an object in circular orbit

T2/r3 = 4π2/GMs

Kepler’s 3rd Law

vescape = √2GMe/Re=√2gRe

Escape Velocity