Chapters 09, 10 Circular Motion, Center Of Gravity

Videos

A video showing an example of a "banked turn".  A component of the normal force from the track helps the biker make a turn.

Riders in this ride at an amusement park stick to the wall of a large circular rotating room.

W/S 9-3 Bob is in a rotating space habitat.  Susie is floating in space outside the habitat.  How do they see each other moving?

These videos demonstrate what happens when the centripetal force goes away.  Objects leave the circular path tangent to the circle and move off in a straight line.

    Water droplets leave a bicycle tire

    A toy car in space leaves a circular track

This video demonstrates the tension in a rope when an object is swinging is greater than if it was just hanging.

This puck made of dry ice decreases its tangential velocity (Vt) as it revolves due to a small amount of friction between the puck and the table.  The constant centripetal force (Fc) is provided by a hanging weight under the table connected to the string.  For a constant Fc, radius(r) of the circle will decrease as Vt decreases, according the the equation Fc=mvt2/r.

Here I increase the centripetal force (Fc) by pulling with my hand on the string beneath the table, forcing a smaller radius (r).  The work done by me transfers energy to the kinetic energy of the puck - it revolves faster and has an increase in tangential velocity, Vt.

Center of Gravity demonstrations.