Q: A 25.0 kg grindstone disc with a 0.250 m radius ( r ) rotates with an angular speed ( ω ) of 30.0 rad/s. When power to the disc is shut off, it decelerates and comes to rest over the course of 20.0 s. When the grindstone is shut off, a speck of dustContinue reading “AP PHYSICS: Rotational Kinematics”
Tag Archives: Rotational Motion
ENERGY AND MOMENTUM: Translational and Rotational Kinetic Energy
When determining the final kinetic energy ( KE ) of falling objects, we need not ( in theory ) concern ourselves with anything other than the linear pathway traveled to the earth’s surface. To the contrary, an object that rolls top to bottom down an incline will gain both linear ( KE ) and rotationalContinue reading “ENERGY AND MOMENTUM: Translational and Rotational Kinetic Energy”
ROTATIONAL MOTION: At What Rate will the Yo-Yo Accelerate?
Several forces must be taken into account to study the motion of a yo-yo. If we assume a hand to be stationary when a yo-yo begins its descent, a tension force acts upward upon the yo-yo’s string. Opposite to the tension force is the force exerted upon the system by the gravitational force of attractionContinue reading “ROTATIONAL MOTION: At What Rate will the Yo-Yo Accelerate?”
ENERGY AND MOMENTUM: Parallel Axis Theorem/Moment of Inertia of a Rod
The moment of inertia ( I ) is the rotational equivalent of mass possessed by an object. This proclamation, however, comes with a caveat: massive objects are not created equal. Different objects of equal mass have differing abilities to resist changes in rotational motion. Additionally, the location of an object’s axis of rotation influences itsContinue reading “ENERGY AND MOMENTUM: Parallel Axis Theorem/Moment of Inertia of a Rod”
ROTATIONAL MOTION: What Distance Separates Two Projectiles Revolving Around a Common Center of Mass?
Q: Two projectiles separated by distance ( dt ) revolve around their center of mass ( cm = ½ dt ). Each projectile has a mass ( m ) of 4.81 x 1020 kg, and they have an instantaneous rotational speed ( ⍵ ) of 1.25 x 10-10 rad/s relative to the center of mass.Continue reading “ROTATIONAL MOTION: What Distance Separates Two Projectiles Revolving Around a Common Center of Mass?”
RENAISSANCE PHYSICS 