1. ESC020: Rigid Body Mechanics
Kinetics of Particles
Normal and Tangential Coordinates
Cylindrical Coordinates
ESC020: Rigid Body Mechanics

2. ESC020: Rigid Body Mechanics
Example 1
The 150lb man lies against the cushion for which the coefficient of static friction is μs=0.5. determine the resultant normal and frictional forces the cushion exerts on him if, due to rotation about the z axis, he has a constant speed v=20ft/s. Neglect the size of the man. Take θ=60°
ESC020: Rigid Body Mechanics

3. ESC020: Rigid Body Mechanics
Example 2
The 150lb man lies against the cushion for which the coefficient of static friction is μs=0.5. If he rotates about te z axis with a constant speed v=30ft/s, determine the smallest angle θ of the cushion at which he will begin to slip off.
ESC020: Rigid Body Mechanics

4. ESC020: Rigid Body Mechanics
Example 2
A conical pendulum consists of a 10 lb sphere supported by a 6ft cord that revolves about a vertical axis with a constant angular velocity so that the string is inclined 30° to the vertical. Determine the tension T in the string and the linear velocity of the sphere.
ESC020: Rigid Body Mechanics

5. Free Body – Mass Acceleration Diagrams
ESC020: Rigid Body Mechanics