Rotational Equilibrium and Dynamics Russ Ballard Kentlake Science Department

Kentlake Science2 Topics Torque Rotation and inertia Rotational dynamics Simple machines

Kentlake Science3 Torque Extended objects Rotation Translation Net torque produces rotation. Depends on force and lever arm.

Kentlake Science4 Torque Measure of a force to rotate an object. Magnitude of applied force. Length of the lever arm. τ = F d (sinθ).

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7 Torque Sign is (+) if counter-clockwise. Sign is (-) if clockwise.

Kentlake Science8 Rotation and Inertia Moment of inertia will resist changes in rotational motion. For a non-point object to be in compete equilibrium ΣF rot = 0 ΣF trans = 0

Kentlake Science9 Rotation and Inertia Center of mass Moment of inertia rotational analog of mass. Mass is distributed over an extended object.

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Kentlake Science14 Rotational Dynamics τ = I α Analog to F = ma I is analog to mass α is analog to acceleration

Kentlake Science15 Rotational Dynamics L = Iω Rotating object has angular momentum Momentum is conserved

Kentlake Science16 Simple Machines Provide mechanical advantage. Alter force or distance not both.