Angular Momentum Essays -- Physics

Angular momentum and its properties were devised over time by many of the great minds in physics. Newton and Kepler were probably the two biggest factors in the evolution of angular momentum. Angular momentum is the force which a moving body, following a curved path, has because of its mass and motion. Angular momentum is possessed by rotating objects. Understanding torque is the first step to understanding angular momentum.Torque is the angular "version" of force. The units for torque are in Newton-meters. Torque is observed when a force is exerted on a rigid object pivoted about an axis and. This results in the object rotating around that axis. "The torque ? due to a force F about an origin is an inertial frame defined to be ? ? r x F"1 where r is the vector position of the affected object and F is the force applied to the object.To understand angular momentum easier it is wise to compare it to the less complex linear momentum because they are similar in many ways. "Linear momentum is the product of an object's mass and its instantaneous velocity. The angular momentum of a rotating object is given by the product of its angular velocity and its moment of inertia. Just as a moving object's inertial mass is a measure of its resistance to linear acceleration, a rotating object's moment of inertia is a measure of its resistance to angular acceleration."2 Factors which effect a rotating object's moment of inertia are its mass and on the distribution of the objects mass about the axis of rotation. A small object with a mass concentrated very close to its axis of rotation will have a small moment of inertia and it will be fairly easy to spin it with a certain angular velocity. However if an object of equal mass, with its mass more spread out from the axis of rotation, will have a greater moment of inertia and will be harder to accelerate to the same angular velocity.3To calculate the moment of inertia of an object one can imagine that the object is divided into many small volume elements, each of mass ?m. "Using the definition (which is taken from a formula in rotational energy) I=?ri2?mi and take the sum as ?m?0 (where I is the moment of inertia and ri is the perpendicular distance of the infinitely small mass' distance from the axis of rotation). In this limit the sum becomes an integral over the whole object:I = lim ?ri2?mi = ? r2 dm. To evalua... ...ne to follow the transferal of rotational energy to and from linear or other forms of energy.Angular momentum is used to explain many things, and it is has many applications. Angular momentum is also essential to our very existence, without the conservation of angular momentum we might drift into the sun or away into space. Angular momentum is a very important part of physics and physics is a very important part of angular momentum.ENDNOTESRaymond A. Serway, Physics For Scientists and Engineers, (Toronto: Saunders College Publishing, 1996) p. 325.David G. Martindale, Fundamentals of Physics: A Senrior Course, (Canada: D.C. Heath Canada Ltd., 1986) p. 320.ibidRaymond A. Serway, Physics For Scientists and Engineers, (Toronto: Saunders College Publishing, 1996) p. 325. Bibliography Blott, J. Frank, Principles of Physics: Second Edition Publisher not given: 1986 David G. Martindale., Fundamentals of Physics, Canada: D.C. Heath Canada Ltd. 1986 Olenick, P. Richard, The Mechanical Universe: Introduction to Mechanics and Heat, Cambridge: Cambridge University Press 1985 Serway A. Raymond, Physics For Scientists and Engineers, Toronto: Saunders College Publishing, 1996