Equations Just like kinematics!!! CircularLinear  0 +  t + ½  t 2 d=d 0 + vt + ½ at 2  0 +  t v=v 0 + at  2 =   v 2 = v a  d  =  /  ta=  v/  t Torque;  = I  Force; F = ma Circular motion: v t = 2  r/T =  r ; tangential velocity  = 2  /T (rad/sec); angular velocity T is time to make one rotation or revolution, one rotation or revolution is 2  radians Gravity: F = GmM/r 2

Acceleration in circular motion Three types –Angular How fast it spins faster –Tangential Linear acceleration at an instant –Centripetal Toward center of rotation For now we’ll concentrate on Angular and treat it just as we did in kinematics; –Mommy, daddy etc.

Definitions  =  /  t; angular acceleration, (rad/sec 2 )  greek letter “the fish”  = torque, “twisting force” units are N. m. Force at a distance, think turning a wrench to tighten a bolt. I = moment of inertia, like mass, only distribution of mass is important.

Moment of Inertia I = sum of mass times radius from axis of rotation. Fun calculus problems! It has been cataloged for common shapes with uniform density.

Common I values (units ?)

Worksheet! Yeah