Ch10 Review - in a time interval t , its average angular...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Print this page Angular Position To describe the rotation of a rigid body about a fixed axis, called the rotation axis , we assume a reference line is fixed in the body, perpendicular to that axis and rotating with the body. We measure the angular position θ of this line relative to a fixed direction. When θ is measured in radians , (10-1) where s is the arc length of a circular path of radius r and angle θ . Radian measure is related to angle measure in revolutions and degrees by (10-2) Angular Displacement A body that rotates about a rotation axis, changing its angular position from θ 1 to θ 2 , undergoes an angular displacement (10-4) where Δ θ is positive for counterclockwise rotation and negative for clockwise rotation. Angular Velocity and Speed If a body rotates through an angular displacement
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: in a time interval t , its average angular velocity avg is (10-5) The (instantaneous) angular velocity of the body is (10-6) Both avg and are vectors, with directions given by the right-hand rule of Fig. 10-6. They are positive for counterclockwise rotation and negative for clockwise rotation. The magnitude of the body's angular velocity is the angular speed . Angular Acceleration If the angular velocity of a body changes from 1 to 2 in a time interval t = t 2- t 1 , the average angular acceleration avg of the body is (10-7) The (instantaneous) angular acceleration of the body is (10-8) Page 1 of 1 Review & Summary 12/23/2010 http://edugen.wiley.com/edugen/courses/crs4957/halliday9118/halliday9118c10/aGFsbGl. .....
View Full Document

Ask a homework question - tutors are online