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RP10-1) Consider an ice hockey puck and a street hockey puck. They both have equal mass and their mass centers are traveling with equal linear velocities as shown in the figure. Which one has the greater linear momentum?
Which one has the greater angular momentum with respect to its mass center?
RP10-2) An externally applied force cannot change the angular momentum of a spinning object.
RP10-3) No matter where a force is applied, it will have the same effect on the angular momentum.
RP10-4) A bar and particle of the same mass m and translating perpendicular to each other collide. Immediately preceding the collision they are traveling with the same speed v. The particle strikes the bar near the edge and adheres to the bar. Which kinetic analysis approach would you employ to determine the linear and angular velocities of the system immediately after the collision?
RP10-5) A 24-kg ladder is released from rest in the position shown. You may model the ladder as a slender uniform bar and neglect friction. If you wish to determine the angular acceleration of the ladder at the instant of release, which kinetic analysis approach would you employ?
RP10-6) The 1-kg uniform slender bar and 2-kg disk shown are released from rest when the bar is horizontal. The disk rolls without slip on the curved surface shown. If you wish to determine the bar’s angular velocity when the bar is vertical, which kinetic analysis approach would you employ?
RP10-7) The 5-kg rectangular plate shown rests on a smooth horizontal surface when the two large impulsive forces displayed, FA = 1000 N and FB = 500 N, are applied to the plate at the angles of θ = 45o and φ = 30o. Determine the angular velocity of the plate and the velocity of its mass center after the forces have been applied for 0.02 seconds. You may assume the plate moves a negligible distance during the application of the forces.
RP10-8) An alternative to using thrusters for controlling satellite orientation is to use reaction wheels. Each reaction wheel is firmly attached to the satellite and essentially consists of a motor driving a heavy flywheel. Reaction wheels are advantageous in that they don’t require propellant (they are powered from the solar panels) and they can position a satellite with high accuracy. Consider a 1200-kg satellite with a radius of gyration with respect to the mass center of 0.85 m about the z-axis with a reaction wheel actuator that includes a 10-kg flywheel of radius 0.2 m. If the system is initially at rest and the flywheel is spun up to 10,000 rpm, determine the resulting angular velocity of the satellite. You may neglect the mass of the rest of the reaction wheel assembly.
