9 53 63 Question 10 A A motor rotates an axle that is connected to one end of a rod, as shown in the figure. Students may adjust the speed at which the motor causes the axle and rod to rotate. During an experiment, what essential quantity or quantities should be measured or determined in order for the students to determine the rod's change in angular momentum after 8 s? Justify your selection. (C) Rod D Motor The mass of the rod, because the mass is related to the net force that is exerted on the rod. The length of the rod, because the length of the rod is related to the rotational inertia of the rod. The average net torque applied to the rod, because the average net torque is related to the change in angular velocity of the rod. The average net force applied to the rod, because the average net force is related to the impulse of the rod. > Q ? O □

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A 150 g ball and a 200 g ball are connected by a 37-cm -long, massless, rigid rod. The balls rotate about their center of mass at 120 rpm. Part A What is the speed of the 150 g ball? Express your answer to two significant figures and include the appropriate units. HA ? Value Units

Modem wind turbines generate electricity from wind power. The large, massive blades have a large moment of inertia and carry a great amount of angular momentum when rotatingA wind turbine has a total of 3 bladesEach blade has a mass of m 5500 kg distributed uniformly along its length and extends a distance r = 49m from the center of rotationThe turbine rotates with a frequency of f= 15 rpm. Part a: enter expression for the total moment of inertia of the wind turbine about its a is of rotation in terms of the define quantites Part b calcukate the total moment of inertia of the wijd turbine about its axis in units of kilogram meter square Part c enter an expression for the expression for the angular momentum of the wind turbine in terms of the defined quantities Part d : calculate the angular momentum of rhe wind turnine in units if kilogram meters squared per second

The shaft of an elevator motor turns clockwise at 180 rpm for 10 s, is at rest for 15 s, then turns counterclockwise at 240 rpm for 12.5 s. What is the angular displacement of the shaft during this motion? Draw angular position and angular velocity graphs for the shaft’s motion

A solid metal disk with moment of inertia I, radius R, and mass m1 can rotate freely about a frictionless axis passing through its center. A light string is wrapped around the disk and connects to a hanging mass m2. The hanging mass is released from rest at a distance d above the ground and accelerates downward with acceleration awhile the disk rotates through an angle q. a)  Draw free body diagrams for the disk and the hanging mass. b) Find an expression for the angular accelerationaof the diskin terms of m2, I, R, and any necessary constants. c) Find an expression for the time it takes for the hanging mass to reach the ground. Write your answer in terms of q, a, and any necessary constants.