Predicting the Position of a Rotating System

(claimed by Anna Marie Whitacre, awhitacre7)

Visual of a rotating system.

In order to provide a cohesive and detailed model of the motion of a rotating object (including Systems with Zero Torque and Systems with Nonzero Torque) it is necessary to predict the position of the system.

The Main Idea

The position of a rotating system can be predicted by predicting the angle over which the object will rotate though out time. Basically, the key to finding out how much a rotating object has moved (over a specific time interval) is the angle through which it moves.

A Mathematical Model

Given that the system in question is indeed rotating, the update form of The Angular Momentum Principle is always applied about the the center of mass in our calculations.

The update form of the Angular Momentum Principle is as follows: [math]\displaystyle{ \vec{L}_{rot,f}=\vec{L}_{rot,i}+\vec{\tau}_{net}\Delta t }[/math] where [math]\displaystyle{ {L} }[/math] is rotational angular momentum and [math]\displaystyle{ \tau }[/math] is net torque from the surroundings.

In basic situations, the update form of the Angular Momentum Principle can further be simplified to account for The Moments of Inertia, [math]\displaystyle{ I }[/math], and the Angular Velocity, [math]\displaystyle{ \omega }[/math] of the rotating system. This simplification of the update form of the Angular Momentum Principle yields the following mathematical equation: [math]\displaystyle{ I\omega _{f}=I\omega _{i}+RF\Delta t }[/math] where net torque, [math]\displaystyle{ \vec{\tau}_{net} }[/math] is simplified to the product of all the forces acting on the system and the locations to which these forces are applied, [math]\displaystyle{ RF }[/math].

A Computational Model

How do we visualize or predict using this topic. Consider embedding some vpython code here Teach hands-on with GlowScript

Examples

Be sure to show all steps in your solution and include diagrams whenever possible

Connectedness

Industrial Application

Mickey's Fun Wheel.

Colossus at Six Flags

In the theme and amusement park industry (e.g. Six Flags and Disney World), the aforementioned method of predicting the position of a rotating system can be applied to determine how far a certain rider has moved on either Mickey's Fun Wheel or Colossus. This prediction of a rider's position after a certain amount of time could be applied by economists to determine the ideal speed and time interval to run their respective ferris wheels to yield an optimal economic profit with respect to the cost of admission tickets.

Scientific Application

Magnetic field produced by current

Orbiting electron

Predicting the position of a rotating system can also pioneer revelations in scientific research fields (esp. biochemistry and chemistry). Given that the position of an electron in relation to the nucleus of a hydrogen atom can be predicted based upon the angular momentum of the electron, this technique can be applied to determining the magnetism exhibited by the electron with respect to some defined axis. Therefore, the relationship between the position of an electron at a certain time (at some distance from a defined axis) could be related to the electric current produced by a magnetic field at that same time.

History

Put this idea in historical context. Give the reader the Who, What, When, Where, and Why.

See also

The Angular Momentum Principle

The Moments of Inertia

Angular Velocity

Systems with Zero Torque

Systems with Nonzero Torque

Further reading

Judd, Brian R. Angular Momentum Theory for Diatomic Molecules. Academic Press, 1975. Print.

External links

Internet resources on this topic

References

Chabay, Ruth W., and Bruce A. Sherwood. Matter & Interactions. Hoboken, NJ: Wiley, 2015. 443-45. Print.

Angular Momentum of an Electron in an H Atom