Newton's first law: An object stays at rest or in steady motion unless acted on by a net force
Newton's second law: F = m x a
Newton's third law: For every action there is an equal and opposite reaction
Speed: speed = distance / time
Acceleration: a = (final velocity - initial velocity) / time
Weight: W = m x g
Momentum: p = m x v
Work: W = F x d
Power: P = W / t
Kinetic energy: KE = 1/2 m v squared
Gravitational potential energy: PE = m x g x h
Density: density = mass / volume
Pressure: P = F / A
Ohm's law: V = I x R
Electric power: P = I x V
Wave speed: v = f x wavelength
Frequency and period: f = 1 / T
Universal gravitation: F = G m1 m2 / r squared
Einstein's mass-energy equivalence: E = m c squared
Law of conservation of energy: Energy cannot be created or destroyed, only changed in form
Law of conservation of momentum: Total momentum stays the same in a closed system
Hooke's law: The force of a spring is proportional to how far it is stretched: F = kx
Archimedes' principle: The buoyant force equals the weight of the fluid displaced
Pascal's principle: Pressure applied to a confined fluid is passed on equally
Bernoulli's principle: Faster-moving fluid has lower pressure
Boyle's law: At constant temperature, gas pressure goes down as volume goes up
Charles's law: At constant pressure, gas volume goes up as temperature goes up
Snell's law: Describes how light bends when it passes between materials
Law of reflection: The angle of incidence equals the angle of reflection
Coulomb's law: Electric force depends on charges and on distance squared
First law of thermodynamics: Energy is conserved; heat and work change internal energy
Second law of thermodynamics: Heat flows from hot to cold, and entropy tends to increase
Third law of thermodynamics: A system cannot be cooled to absolute zero in a finite number of steps
Kepler's first law: Planets orbit in ellipses with the Sun at one focus
Kepler's second law: A planet sweeps out equal areas in equal times
Kepler's third law: A planet's orbital period squared is proportional to its distance cubed
Centripetal acceleration: a = v squared / r
Average velocity: (final position - starting position) / time
Distance at constant acceleration from rest: d = 1/2 a t squared
Final speed from rest: v = a x t
Series circuit resistance: Total R = R1 + R2 + R3
Parallel circuit resistance: 1/R total = 1/R1 + 1/R2 + ...
Kinetic energy depends on speed how?: On the square of speed, so doubling speed quadruples KE
Mechanical advantage: Output force divided by input force
Efficiency: (useful output / total input) x 100 percent
Heat energy: Q = m c (change in temperature)
Specific heat capacity: Heat needed to raise 1 kg of a substance by 1 degree
Ideal gas law: PV = nRT
Doppler effect: The pitch or color of a wave changes when the source or observer moves
Heisenberg uncertainty principle: You cannot know a particle's exact position and momentum at once
Photon energy: E = h x f (Planck's constant times frequency)
Torque: Torque = force x distance from the pivot
Impulse-momentum: Force x time = change in momentum
Escape velocity: The speed needed to break free of a planet's gravity
Universal gravitational constant: G, about 6.67 x 10^-11 N m2/kg2

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