Question 3 1 pts Suppose an ice skater, such as the one in the figure, is spinning at 0.779 rev/s with her arms extended. She has a moment of inertia of 2.24 kg. m with her arms extended and of 0.333 kg - m with her arms close to her body. (These moments of inertia are based on reasonable assumptions about a 60.0-kg skater.) What is her angular velocity in revolutions per second after she pulls in her arms? (a) L= 100 L=1'00' Assume 3 significant figures in your answer. Question 1 1 pts A freight train accelerates from rest, giving its 0.351 -m-radius wheels a constant angular acceleration of 0.312 rad/s. How far has the train moved down the track after 57.2 seconds? Assume rolling without slipping. 3 significant figures in your answer. 1 pts A person is riding a bicycle, and its wheels have an angular velocity of 28.2 rad/s. Then, the brakes are applied and the bike is brought to a uniform stop. During braking, the linear displacement of each wheel is 8.4 m. What is the magnitude angular acceleration (in rad/s) of each wheel, if the radius of each wheel is 0.6 m? Answer to 3 sig figs. Question 2 The figure below shows a man holding a pole that has a mass of 6.9 kg. His right had exerts an upward force FR at a point that is 49cm to his right from the center of gravity of the pole. His left hand exerts an upward force of F at a point that is 20.5cm to his left of the center of gravity. Solve for the magnitude of F in Newtons. FR CG F W W Assume 3 significant figures in your answer. Free-body diagram Two disks are rotating about the same axis. Disk A has a moment of inertia of 5.87 kgm and an angular velocity of +3.4 rad/s. Disk B is rotating with an angular velocity of -6.49 rad/s. The two disks are then linked together without the aid of any external torques, so that they rotate as a single unit with an angular velocity of -1.12 rad/s. The axis of rotation for this unit is the same as that for the separate disks. What is the moment of inertia of disk B? Wo A Round to 3 sig figs. WE A & B B A person is holding a physics book in their outstretched hand as shown below. Calculate the magnitude of the force FB that is exerted the biceps muscle in order to hold the book stationary if the mass of the arm is ma = 3.25 kg and the distance from the book to the elbow is r3 = 43.8 cm. Triceps muscle Biceps muscle PHYSICS m = 4.0 kg CG 4.0 cm 16 cm m = CG Wa ra (a) W CG CG W (b) Assume 3 significant figures in your answer. Free-body diagram