PHY 2414 Chapter 8 Rotational Motion Flashcards

Flashcards covering conceptual questions from Chapter 8 on Rotational Motion.

Rigid Object Rotation

All points in a rigid object rotating about a fixed axis have the same angular speed and angular acceleration.

Merry-Go-Round Riders

Points at different distances from the axis of rotation have the same angular speed, but the point farther away has a greater tangential speed.

Linear Speed of Points on a Tire

The highest point: 130 mph, the lowest point: 0 mph, the center: 65 mph

Moment of Inertia of Objects

Object B has the greatest moment of inertia when rotated about an axis perpendicular to the plane of the drawing at point P.

Hoop Kinetic Energy

For a uniform hoop rolling without slipping, translational kinetic energy and rotational kinetic energy are equal.

Sphere Kinetic Energy

For a solid uniform sphere rolling without slipping, translational kinetic energy is larger than rotational kinetic energy.

Kinetic Energy Comparison: Sphere vs. Cylinder

A solid sphere's total kinetic energy is less than the total kinetic energy of a solid cylinder when both have the same mass and radius and roll without slipping at the same forward speed.

Disk vs. Hoop on Incline

A disk reaches the bottom of an inclined plane first if both a disk and a hoop of the same mass and radius are released at the same time and roll without slipping.

Sphere vs. Cylinder vs. Pipe on Incline

A sphere will reach the bottom first when a solid sphere, solid cylinder, and hollow pipe with equal masses and radii are released simultaneously at the top of an inclined plane and do not slip.

Order of Objects Reaching Bottom of Incline

Sphere, disk, then hoop.

Disk vs. Sphere on Incline

The sphere will reach the bottom first.

Torque and Force Magnitude on Door

The force applied at the midpoint has a greater magnitude.

Torque and Force Angle on Door

The force applied perpendicular to the door exerts the greater torque about the door hinge.

Torque and Force Application

Case 1 has the greatest torque about the pivot P due to the applied force.

Extending Arms on Spinning Stool

Her moment of inertia increases and her angular speed decreases.

Moving to Center of Merry-Go-Round

The moment of inertia of the system decreases, and the angular speed increases.

Units of kg ∙ m^2/s

Angular momentum

Units of kg ∙ m^2/s^2

Work, Rotational Kinetic Energy, and Torque

Spinning Skater Pulling in Arms

Her angular momentum remains constant.

Direction of Angular Velocity of Bicycle Wheels

To your left.