Frictional Torque on a Rotating Disc

Abstract

Resistance to motion often includes a dry frictional term independent of the speed of an object and a fluid drag term varying linearly with speed in the viscous limit. (At higher speeds, quadratic drag can also occur.) Here measurements are performed for an aluminium disc mounted on bearings that is given an initial twist and allowed to spin until it comes to a stop. It is found that a sum of both the dry and fluid resistive terms are needed to accurately fit the entire data. However, the speed-independent term alone suffices over any suitably limited range of motion, permitting one to use the standard kinematic equations for constant angular acceleration. The measurements and theory are appropriate for an introductory physics laboratory at the college level.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2012
Accession Number
ADA563817

Entities

People

  • Carl E. Mungan

Organizations

  • United States Naval Academy

Tags

DTIC Thesaurus Topics

  • Aluminum
  • Angular Acceleration
  • Coefficients
  • Drag
  • Electronic Mail
  • Elements
  • Equations
  • Experimental Data
  • Friction
  • Information Operations
  • Leading Edges
  • Measurement
  • Physics
  • Physics Laboratories
  • Revolutions
  • Standards
  • United States Naval Academy

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