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Chapter 8: Dynamics II: Motion in a Plane. 8.2 Velocity and Acceleration in Uniform Circular Motion 8.3 Dynamics of Uniform Circular Motion 8.7 Nonuniform Circular Motion. Stop to think 8.2 P 214 Stop to think 8.3 P 219 Stop to think 8.4 P 226 Stop to think 8.5 P 228. Example 8.3 P215
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Chapter 8: Dynamics II: Motion in a Plane 8.2 Velocity and Acceleration in Uniform Circular Motion 8.3 Dynamics of Uniform Circular Motion 8.7 Nonuniform Circular Motion
Stop to think 8.2 P 214Stop to think 8.3 P 219Stop to think 8.4 P 226Stop to think 8.5 P 228 • Example 8.3 P215 • Example 8.5 P217 • Example 8.6 P218 • Example 8.7 P227
Dynamics of Uniform Circular Motion • From the Newton’s second law, a particle of mass m moving at constant speed V around a circle of radius r must have a net force of magnitude (mV2/r) pointing toward the center of the circle
Ex. 8.3 Spinning in a circle • An Energetic father places his 20 Kg child on a 5.0Kg cart to which a 2.0-m-long rope is attached. He then holds the end of the rope and spins the cart and child around in a circle, keeping the rope parallel to the ground. If the tension in the rope is 100N, how many revolutions per minute (rpm) does the cart make?
Problem 46: Mass m1 on the frictionless table is connected by a string through a hole in the table to a hanging mass m2. With what speed must m1 rotate in a circle of radius r if m2 is to remain hanging at rest? • If m2 remains hanging at rest • T-m2·g=0 • (2) For m1, N = m1·g • T =m1 V2 /r
A roller coaster car going around a vertical loop-the loop of radius r. We’ll assume that the motion makes a complete circle and not worry about the entrance to and exit from the loop. Why doesn’t the car fall off at the top of the circle
Problem 8.62, A small ball rolls around a horizontal circle at height y inside a frictionless hemispherical bowl of radius R., find an expression for the ball’s angular velocity in terms of R, y, g