Consider a situation where an ice skater spins without friction in the ice with her arms outstretched. Then he picks up his arms to his body, reducing his moment of inertia. Its angular momentum is preserved, so as it reduces its moment of inertia, it increases its angular velocity and rotates faster. Compared to hers initial rotational kinetic energy, what is hers final rotational kinetic energy like? explain with fundamentals of physical

Given a mass of 380 grams, and a rotational speed 180 rpm, calculate the maximum rotational kinetic energy for the following three shapes: a disk, a sphere and a thin rod.  Both, the disk and the sphere have a radius of 20 cm, and the length of the thin rod is 40 cm.  If the same mass is shaped as a hoop with a radius of 20 cm, would be the rotational kinetic energy greater, or smaller than the kinetic energies calculated for the other 3 shapes? Check your prediction - calculate the rotational kinetic energy for that shape, and compare your results. Was your answer consistent with your expectations?

A large plate is initially rotating about an axis through its center with angular velocity of 3w, as shown in the figure. The upper plate is initially not rotating and has the same mass but half the radius as the large plate. The small plate is lowered onto the large plate, and after a short time they will rotate together and willI have the same final angular velocity. Which of the following best describes the ratio of the kinetic energy of the system before the collision to after the collision (Ratio KEbefore KEafter %D 3w. 1.50 1.25 1.00 0.80 0.67

This problem illustrates the two contributions to the kinetic energy of an extended object: rotational kinetic energy and translational kinetic energy. You are to find the total kinetic energy Ktotal total of a dumbbell of mass m when it is rotating with angular speed ω and its center of mass is moving translationally with speed v. (Figure 1)Denote the dumbbell's moment of inertia about its center of mass by Icm. Note that if you approximate the spheres as point masses of mass m/2 each located a distance r from the center and ignore the moment of inertia of the connecting rod, then the moment of inertia of the dumbbell is given by Icm=mr2, but this fact will not be necessary for this problem.  Find the total kinetic energy Ktot of the dumbbell. Express your answer in terms of m, v, Icm, and ω.

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A 1.10-kg particle moves in the xy plane with a velocity of Need Help? Read It = (3.70 1-3.70 ĵ) m/s. Determine the angular momentum of the particle about the origin when its position vector is = (1.50 î+ 2.20 ĵ) m. k) kg - m²/s Watch It

a) A diver leaps from a platform and immediately goes into a tuck position. If we assume that the diver has an initial angular velocity of 7.5 rad/sec, and has an angular acceleration of -0.22rad/sec2,how long will it take for the diver to complete 2 full revolutions?b) Assume that the diver is 6 m above the water with an initial vertical velocity of 1.74 m/s when she begins to rotate. Will she be able to complete 2 full revolutions before hitting the water? Why or why not?

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A rotating solid sphere, (mass = 1kg, radius = 25 cm) starts to spin from rest with a constant angular acceleration of a =1.5 rad / s². After 5s, what is: • The angular velocity of the sphere • The number of rotations (please include fractional answers) The rotational kinetic energy of the sphere if I =MR

A uniform solid sphere, of radius R = 1.0 m and mass M = 5.0 kg, rotates freely with a constant angular speed o = 2.0 rad/s about a vertical axis tangent to the surface of the sphere, as shown in Figure . Find the rotational kinetic energy of the sphere. A) 14 J В) 10 J C) 22 J D) 28 J E) 36 J SIxe