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Unformatted text preview: ch other on an
axle that passes through the
center of each. Calculate the net
torque on this compound wheel
due to the two forces shown,
each of magnitude 50 N.
Counterclockwise is positive Example
Two forces (FB = 20 N and FA = 30N) are applied on a
meter stick which can rotate about its left end. Force
FB is applied perpendicularly at the midpoint. Which
force exert the greater torque or both the same? Rotational Dynamics; Torque and Rotational Inertia Multiply both sides by R The quantity mR2 represent the Moment of Inertia Take a solid cylinder and think of each point on the cylinder as a particle in rotation at a different position from the center. Axis ﬁxed Rotational Inertia (continued) In this case the summation is called the Moment of Inertia of the object Combining the above equations we obtain Newton’s Second Law for Rotation This relation is valid for rotation of a solid about a ﬁxed axis. If the axis moves like a ball rolling down a ramp we
can write.
Here the axis direction is fixed but the axis may accelerate The moment of inertia is a measure of the rotational inertia of an object Two small weights of mass 5.0 kg
and 7 kg are mounted 4.0 m apart
on a light rod (whose mass can be
ignored) as shown. Calculate the
moment of inertia of the system (a)
when rotated about an axis half way
between the weights, and (b) when
rotated about an axis 0.50 m to the
left of the 5...
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This note was uploaded on 02/03/2014 for the course PHYSICS 1061 taught by Professor Tsankov during the Fall '09 term at Temple.
 Fall '09
 tsankov
 Physics

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