A circular disk with a radius of 0.43 m is subject to 2 tangentially applied forces. The disc is fixed such that it will rotate about its center. Both forces produce a torque in the same direction. The mass of the disc is 0.62 kg. The moment of inertia of a disc is  I = (1 / 2 )MR^2 F1 = 2.2 N applied at the outer edge of the disc. F2 = 5.4 N applied at a distance of 0.21 from the center of the disc. What is the angular acceleration of the disc?

A circular disk with a radius of 0.38 m is subject to 2 tangentially applied forces. The disc is fixed such that it will rotate about its center. Both forces produce a torque in the same direction. The mass of the disc is 0.73 kg. The moment of inertia of a disc is I =1/2MR^2 F1 = 2.3 N applied at the outer edge of the disc. F2 = 3.6 N applied at a distance of 0.29 from the center of the disc. What is the angular acceleration of the disc?

In the figure, block 1 has mass m1 = 0.460 kg, block 2 has mass m2 = 0.500 kg, and the pulley, which is mounted on a horizontal axle with negligible friction, has radius R = 0.0500 m. Tension T1, the tension force on block 1, is 4.54N. Tension T2, the tension force on block 2, is 4.87N. What is the net torque acting on the pulley? Please note that I know that the answer is to be that taunet = -T1R + T2R Why is the torque associated with T1 negative when it produces a counterclockwise rotation, and the torque associated with T2 positive when it produces a clockwise rotation? I thought that if the direction of rotation was counterclockwise, then the torque is positive, and if the direction was clockwise, then the torque is negative.

If you hold your arm outstretched with your palm upward, the force to keep your arm from falling comes from your deltoid muscle. Assume that the arm with hand has mass 4.25 kg and the distances and angles shown. What is the magnitude of the torque must the deltoid muscle provide to keep the arm in this position, in N·m? Use g = 10.0 m/s2. Your answer needs to have 3 significant figures, including the negative sign in your answer if needed. Do not include the positive sign if the answer is positive. No unit is needed in your answer, it is already given in the question statement.