Class 7 relative motion and fixed axis rotation

# Comparetowhatyouwouldgetwith thentorrqsystem contact

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

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: the initial values of the body’s angular position and angular velocity. Note these equations are very similar to the constant acceleration relations developed for the rectilinear motion of a particle. 1. The disk is supported by a stationary pin at its center, i.e it spins about C without translating. Given the angular velocity and acceleration, compute the velocity and acceleration vectors of points A and D using the vector approach and an x­y­z coordinate system. Compare to what you would get with the n­t or r­q system. Contact • When two points are in contact (without slipping): o o o Their velocity is the same Their tangential acceleration is the same Their normal acceleration is NOT EXAMPLE Given: The motor turns gear A with a constant angular acceleration, αA = 4.5 rad/s2, starting from rest. The cord is wrapped around pulley D which is rigidly attached to gear B. Find: The acceleration of cylinder C Plan: 1) The angular acceleration of gear B (and pulley D) can be related to αA. 2) The acceleration of cylinder C can be determined by using the equations of motion for a point on a rotating body since (at)D at point P is the same as ac. What is the tangential acceleratio...
View Full Document

## This document was uploaded on 04/01/2014.

Ask a homework question - tutors are online