Physics 111: Elementary Mechanics

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Physics 111 Elementary Mechanics Lecture 9

• Carsten Denker
• NJIT Physics Department
• Center for SolarTerrestrial Research

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Rotational Variables
Radian Measure
Angular Displacement
Angular Velocity
Angular Acceleration
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Constant Angular Acceleration
Equations of motion for constant angular
acceleration.
Are angular quantities vectors?
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Relating Linear and Angular Variables
Position
Period of Revolution
Speed
Acceleration
(tangential)
(radial)
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Kinetic Energy of Rotation
rotational inertia
kinetic energy
system of particles
solid body
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Rotational Inertia
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Parallel-Axis Theorem
Let h be the perpendicular distance between the
given axis and a parallel axis through the center
of mass. If Icom is the rotational inertia of
the body about the parallel axis that extends
through the bodys center of mass, then the
rotational inertia I about the given axis is