1. Physics 2015: Rotational Motion Purpose Use the principle of conservation of energy to verify that gravitational potential energy can be converted into rotational kinetic energy and linear kinetic energy in a simple experiment. Use the principle of conservation of momentum to explain transfer of momentum during a collision of rotating bodies. Use the principle of conservation of momentum to explain how changing the shape of a rotating body affects the rotational velocity.

2. Physics 2015: Rotational Motion Equivalent quantities in linear versus rotational motion Linear MotionRotational Motion Mass (m)Moment of Inertia (I) Distance (x) Angle ( Ɵ ) Velocity (v)Angular Velocity ( ω ) Acceleration (a)Angular Acceleration ( α ) Momentum (p = mv)Angular Momentum (L = I ω )

3. Physics 2015: Rotational Motion TypeLinear MotionRotational Motion Force Position Velocity Momentum

4. Physics 2015: Rotational Motion Activity I: Rotating Bodies and Conservation of Energy Setup: As hanging mass drops, the plate starts to rotate faster and faster. Task: Design an experiment to determine whether total energy is conserved. Important: Take into account all types of energy you can think of that are relevant here.

5. Physics 2015: Rotational Motion  Note that the “Smart Pulley” (circled below) measures its own angular velocity, which is NOT the same as that of the platter.  The “Smart Pulley’s” angular velocity and the platter’s angular velocity are related. You need to find this relationship.

6. Physics 2015: Rotational Motion Activity II: Collision Between Rotating Bodies Setup: Main platter rotates, auxiliary platter is dropped on top of main platter Task: Design an experiment to determine whether total angular momentum is conserved. Important: You need to turn the main platter upside down as shown in the diagram.

7. Physics 2015: Rotational Motion Activity III: The Spinning “Ice Skater” Setup: U-channel placed on top of platter. Movable weights (little carts with wheels) can be pulled Inwards by a thread. Task: Test conservation of angular Momentum as carts are pulled in. Hint: Threads must be routed through holes on the side of the spindle and come out on the top of the spindle, where you can pull on them upwards.