INSTANTANEOUS CENTER OF ZERO VELOCITYToday’s Objectives:Students will be able to:1.Locate the instantaneous center of zero velocity.2.Use the instantaneous center to determine the velocity of any point on a rigid body in general plane motion.In-Class Activities:•Check Homework•Reading Quiz•Applications•Location of the Instantaneous Center•Velocity Analysis•Concept Quiz•Group Problem Solving•Attention Quiz
READING QUIZ1.If applicable, the method of instantaneous center can be used to determine the __________ of any point on a rigid body.A)velocityB) accelerationC)velocity and accelerationD) force2.The velocity of any point on a rigid body is __________ to the relative position vector extending from the IC to the point.
APPLICATIONSThe instantaneous center (IC) of zero velocity for this bicycle wheel is at the point in contact with ground. The velocity direction at any point on the rim is perpendicular to the line connecting the point to the IC.Which point on the wheel has the maximum velocity?Does a larger wheel mean the bike will go faster for the same rider effort in pedaling than a smaller wheel?
APPLICATIONS(continued)As the board slides down the wall (to the left), it is subjected to general plane motion (both translation and rotation). Since the directions of the velocities of ends A and B are known, the IC is located as shown.How can this result help you analyze other situations?What is the direction of the velocity of the center of gravity of the board?
INSTANTANEOUS CENTER OF ZERO VELOCITY (Section 16-6)