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Kinematics: Formula Cheat Sheet

Every key formula for Kinematics, with what it means and where it comes from.

FormulaWhat it meansTopic
a = (v - u) / tAcceleration equals change in velocity divided by time taken.Acceleration Explained
a = Δv / tAcceleration is the rate of change of velocity.Acceleration Explained
v = g tVelocity after t seconds of free fall from rest.Free Fall and Gravity
s = 1/2 g t^2Distance fallen after t seconds from rest.Free Fall and Gravity
v^2 = 2 g sVelocity squared equals twice g times the distance fallen from rest.Free Fall and Gravity
v_x = v cos θHorizontal component of the launch velocity.Projectile Motion Basics
v_y = v sin θVertical component of the launch velocity.Projectile Motion Basics
range = v_x x time of flightHorizontal distance equals horizontal velocity times time in the air.Projectile Motion Basics
v_AB = v_A - v_BVelocity of A relative to B equals A's velocity minus B's velocity.Relative Velocity
drag = weight at terminal velocityAt terminal velocity, air resistance balances weight, so the net force is zero.Terminal Velocity
v_t = sqrt(2 m g / (ρ A C_d))Terminal velocity depends on mass, air density, area and drag coefficient.Terminal Velocity
v = u + a tFinal velocity equals initial velocity plus acceleration times time.The SUVAT Equations of Motion
s = u t + 1/2 a t^2Displacement equals initial velocity times time plus half acceleration times time squared.The SUVAT Equations of Motion
v^2 = u^2 + 2 a sFinal velocity squared equals initial velocity squared plus twice acceleration times displacement.The SUVAT Equations of Motion
s = 1/2 (u + v) tDisplacement equals average velocity times time.The SUVAT Equations of Motion
speed = distance / timeAverage speed equals total distance travelled divided by time taken.Velocity vs Speed: What's the Difference?
velocity = displacement / timeAverage velocity equals displacement divided by time taken.Velocity vs Speed: What's the Difference?
v = √(2 × g × h)A falling object speeds up steadily under gravity, and its impact speed depends only on the height it fell from.Free Fall Calculator
R = v₀² sin(2θ) ÷ gA projectile's horizontal range depends on its launch speed, launch angle and gravity, with air resistance ignored.Projectile Motion Calculator
v_rel = v₁ − v₂Relative velocity is the difference of the two velocities, and it can be negative when the second object is faster.Relative Velocity Calculator
v = u + a × tWith constant acceleration, velocity grows steadily over time and displacement follows from the starting speed and acceleration.SUVAT Motion Calculator
v_t = √(2 × m × g ÷ (ρ × A × C_d))A falling object stops speeding up when drag equals its weight, so heavier or sleeker objects fall faster at terminal speed.Terminal Velocity Calculator

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