Angular Velocity and Acceleration
A constant force is applied to a frictionless disk giving the disk a constant angular acceleration. The tangential velocity of several points is displayed.

Torque on a Body
A force is applied to an irregularly shaped body on a frictionless, horizontal surface. The location the point of application of the force can be altered by dragging the application-point. The magnitude and direction of the applied force can be altered by dragging its tail. Displayed are the torque, the magnitude and direction of the force, the lever arm, and the angle between the force and the lever arm. Also displayed are the perpendicular values of the applied force and the lever arm.

Torque Comparison
Four identical objects are hinged about the same point on horizontal, frictionless surface. A force is applied to each object with the same lever arm. Both the direction and magnitude of the forces can be varied in order to observe the resulting angular acceleration.

Axe and Grindstone
An ax is applied to a rotating grindstone. The contact forces acting on the grindstone are displayed along with the magnitude of the net torque acting on the grindstone.

Linear and Free Rotational Motion
A "hammer" is tossed into air with some rotational motion. The simulation shows that the center of mass move like a projectile in a parabolic arc while the hammer rotates about its center of mass at a uniform angular velocity.
Free Rotational Motion QTMovie

Energy of a Revolving Rod
A rod is hinged about one end and released from rest. The rod's Rotational Energy about its pivot point is shown to be equal to the kinetic energy of the rod's center of mass plus the rod's rotational energy about its center of mass.

Physical Pendulum
A uniform bar is hinged about a pivot point on the bar that is a distance h from it center of mass. The period of the pendulum can be measured and compared with the small angle predicted period. The location of the pivot point and the initial angular displacement can be dragged to new positions.

Ball Rolling Down an Incline
A ball rolls without slipping down an incline planed tilted at some angle. The various force acting on the ball are displayed along with the rotational equations of motion.

Slipping and Rolling Disk
A disk on a horizontal surface is made to slip by a applied horizontal force. Friction between the surface and the disk eventually causes the disk to roll without slipping. When the disk rolls without slipping you can observe that the velocity of the center of mass is equal to the velocity of the rim of the disk.

Free Motion of a Disk
An applied force acts on a disk that is free to move and rests on a horizontal, frictionless surface. The force is offset from the disk's center of mass. The disk under goes both Rotational and Translational motion. The direction and magnitude of the force can be varied as well as the point of application of the force by dragging. Both the mass and the moment of inertia can be set independently, causing the disk's density to change.

Point on a Turn Table.
The velocity and acceleration of a point on uniformly accelerating turntable are displayed. You can observe the action in either the rest frame or a frame rotating with the turntable. In the rotating frame the velocity vector becomes the tangential velocity and the components of the acceleration vector become the centripetal and tangential acceleration. Block on Turntable Problem

Man on a Plank
A man stands somewhere on a plank supported by two vertical cords. Displayed is the tension in the cords. The position of the man as well as the mass of the plank and the man can be varied. Man on a Plank Problem

Torques on a Disk
Two torques are applied to a disk pivoted about its center. The location, magnitude and direction of the torques can be altered. The resulting torque and angular acceleration are displayed. Torques on a Disk Problem

Slipping Bowling Ball
A rotating bowling ball with no linear motion is dropped onto a rough surface. The ball slips until the linear velocity of its center of mass is equal to the tangential velocity of it outer edge. The ball then rolls without slipping and the net torque on the ball drops to zero. Slipping Bowling Ball Problem

Puck Stick Collision
A moving air puck strikes a stationary stick at right angles on a frictionless air table. The point of collision relative to the center of the stick can be varied along with the initial velocity and masses of the objects. The initial setup is for a case where the puck stop after the collision. In this problem all three conservation laws apply: conservation of energy, momentum, and angular momentum. Puck Stick Collision