Unit Three Content
In this unit, we studied circular motion and the forces surrounding it. We studied circular motion, angular speed, tangential speed, "turning" acceleration, centripetal acceleration, the law of universal gravitation, gravitional fields, and orbital motion.
Uniform Circular Motion
There are two kinds of coordinates, cartesian coordinates, and polar coordinates. Cartesian coordinates are in terms of x and y, while polar coordinates are in radians and angles, which can be converted into each other using specified formulas. Angular displacement is a change in angular position. Arclength is the distance traveled along a curved path (usually a circle). The formula for arc length is s=r*θ. Velocity is angular speed and or tangential speed. Angular speed is a change of angular position over time. Tangential speed is the speed at which an object is moving tangent to the path, which is normally referred to as speed. "Turning" acceleration is acceleration in which the object remains at a constant velocity, but changes directions.
Universal Gravitation
Centripetal acceleration is the acceleration that points towards the center of rotation. The Law of Universal Gravitation was confirmed with the 1798 experiment. Gravity is proportional to the mass of each body and inversely proportional to the square of the distance between the two bodies. Field theories rely on an object creating a "field" that exists everywhere in space. Other objects interact with the field and not the object that generated it. Mass creates a field to determine how other mass interacts (force) with the field source. This is a gravitational field. Orbital motion is the motion of an object in an orbit around a fixed point.
