Rotational Motion

Rotational Motion

1. Energy

   • Energy Bar Graphs
     • Used to show the energy before and after, as well as the system
     • Energy Statement
       • Conserved
         • No outside torques
         • E₀ = E
       • Not Conserved
         • E₀ ≠ E
         • Outside torque acts on the system
       • Used to show if there are outside torques
     • Energy Types
       • Ug
         • Gravitational Energy
         • Regular Motion
           • mgh
         • Orbits
           • (Gm₁m₂)/(r²)
       • Kₜ
         • Translational Energy
         • ½mv²
       • Kᵣₒₜ
         • Rotational Energy
         • ½Iα²
     • System
       • What objects are being affected by the torques
       • Earth
         • If no earth in system, use no Ug

2. Forces

   • ΣF = ma
     • Mass
       • Use Kilograms
     • Linear Variables
       • Bridge Equations
         • α = a/r
         • ω = v/r
       • a
       • v
     • Forces
       • Fₜ
         • Use both rotational and linear 2nd law to solve for
         • Force of tension
       • Fg
         • mg
         • Force of Gravity; always faces straight down
       • Fₙ
         • Normal Force
         • Use both rotational and linear 2nd law to solve for
       • Fₛ
         • Static Friction (no slipping)
         • Use both rotational and linear 2nd law to solve for
   • Στ = Iα
     • Inertia
       • How difficult it is to accelerate an object
       • c mr²
         • Value of c varies based on the shape and type of an object
           • A larger c means a smaller α
     • Rotational Variables
       • α
         • Rotational acceleration
       • ω
         • Rotational Velocity
     • Torque
       • The rotational equivalent of force
       • Fr