A wheel with rotational inertia 0.80 kg m2 has initial angular speed 7.0 rad/s. It slows to a stop because of friction, completing 6.5 revolutions in the process. (a) Find the initial kinetic energy and angular momentum. (b) Use kinetic energy to find the torque due to friction in the axle of the disk. (c) Use the angular momentum to find the external angular impulse acting on the wheel that would accelerate it back to the same speed in 0.50 seconds?

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

A 70 kg disk is spinning about a vertical axis of rotation with a radius of 1.2 m and a rotational inertia of 0.45 mr2 and it has an initial angular velocity of 10 rad/s. An unknown mass falls onto the disk 0.8 m away from the axis of rotation. After the collision, the disk is now spinning at 6 rad/s. The rotational inertia of the mass is mr2. Calculate the unknown mass that falls on the disk.

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 uniform solid ball rolls without slipping down a plane which is inclined at 31° to the horizontal. If the ball has a radius r=0.4m, a mass m=0.1 kg and starts from rest, find: a) the speed of the ball after it travels 2m down the incline.  b) at this point, what is the angular momentum of the ball? c) If the coefficient of friction between the ball and the plane is 0.25, what is the maximum angle of inclination that allows the ball to roll without slipping?

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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

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

If a car tire with a moment of inertia of 4 kg*m² has an initial angular speed of 8 rad/s and then it experiences a net-work of 50 J, what is the final angular speed? O 12.28 rad/sec O9.43 rad/sec O 0.56 rad/sec O 6.24 rad/sec

4. Two identical disks (same mass and radius) have a common axis. Initially one of the disks is spinning with a constant angular velocity. When the two disks are brought into contact, they stick together. Which of the following statements is true? (a) The total kinetic energy and the total angular momentum are unchanged from their initial values. (b) Both the total kinetic energy and the total angular momentum are reduced to half of their original values. (c) The total angular momentum is unchanged, but the total kinetic energy is reduced to half its original value. (d) The total angular momentum is reduced to one-half of its original value, but the total kinetic energy is unchanged. (e) The total angular momentum is unchanged, but the total kinetic energy is reduced to one-quarter of its original value.