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King Fahd University of Petroleum & Minerals. Mechanical Engineering Dynamics ME 201 BY Dr. Meyassar N. Al-Haddad Lecture # 23. Course coverage. Kinematics of particle in various motion. (Chapter 12) Force and acceleration. (Chapter 13) Work and energy relations. (Chapter 14)
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King Fahd University of Petroleum & Minerals Mechanical Engineering Dynamics ME 201 BY Dr. Meyassar N. Al-Haddad Lecture # 23
Course coverage • Kinematics of particle in various motion. (Chapter 12) • Force and acceleration. (Chapter 13) • Work and energy relations. (Chapter 14) • Impulse and Momentum. (Chapter 15) • Kinematics of a rigid bodies. (Chapter 16) • Force and acceleration of a rigid bodies . (Chapter 17) • Work and energy relations of a rigid bodies. (Chapter 18) • Impulse and Momentum of a rigid bodies (Chapter 19)
Chapter 16 Planar Kinematics of a Rigid BodyObjective • To classify the various types of rigid-body. • To investigate rigid-body translation and show how to analyze motion about a fixed axis.
Rigid-Body Motion • Types of rigid body planar motion: • Translation • Rotational about fixed axis • General plane motion
Translation Every line segment on the body remains parallel to its original direction during the motion
Rotation about fixed axis All particles of the body move along circular paths except those which lie on the axis of rotation
General plane motion Combination of translation and rotation
Example Curvilinear translation General plane motion Rectilinear translation Rotation about a fixed axis
Position Velocity Acceleration Translation All points move with same velocity and acceleration
Time dependent acceleration • Constant acceleration Summary chapter 12
Angular Position ( q ) Defined by the angle qmeasured between a fixed reference line and r Measured in rad Angular Displacement Measured as dq Vector quantity Measured in radians or revolutions 1 rev = 2 p rad Rotation About a Fixed axisFor Line
Angular velocity (w ) “the time rate of change in the angular position” Angular acceleration “the time rate of change of the angular velocity” a = f(q)
The arc-length is Motion of Point P Position : Is defined by the position vector r Velocity “tangent to the path”
Acceleration “rate of change in the velocity’s magnitude” “rate of change in the velocity’s direction” Direction of an is always toward O
r1 r2 r1 r2 s , v, a
Example 16-1 Rest at = 4t m/s2 w=? q=?