12. A 0.20 kg block on a 0.50-m-long string swings in a circle on a horizontal, frictionless table at 75 rpm. A. What is the speed of the block? B. What is the tension in the string?

A 700-g rock is attached to a half-meter (massless) string and is spun on the other end on vertical plane. The rock makes a complete revolution every 0.21 seconds. What is the tension of the string at the top of the circular trajectory, and at the bottom of the circular trajectory? What is the difference in total energy at the top and bottom of the trajectory?

Consider an annular disk rolling down an inclined plane. The annular disk has mass 154 [g], inner radius 8.00 [cm] and outer radius 12.0 [cm]. The inclined plane has a slope that forms an angle of 44.6° with the ground. A.  Suppose that the coefficient of static friction ?s is large enough so that the annular disk rolls without slipping. What is the magnitude of the translation acceleration felt by the annular disk's center of mass in the direction parallel to the slope? B. What is the minimum value that the coefficient of static friction ?s must take so that the annular disk rolls without slipping?

A 50 g ball of clay is thrown from the left tangent to the top of a 2.0 kg, 30-cm-diameter sphere that spins at a frequency of 1 rev/s ccw about its center. Assuming that the clay sticks to the sphere, how fast must you throw the clay to ensure that the spinning sphere comes to a stop?

Figure P9.75 shows a 100 g puck revolving at 100 rpm on a 20-cm-radius circle on a frictionless table. A string attached to the puck passes through a hole in the middle of the table. The end of the string below the table is then slowly pulled down until the puck is revolving in a 10-cm-radius circle. How many revolutions per minute does the puck make at this new radius?

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

A flywheel turns through 60 rev as it slows down from an angular speed of 12 rad/s to a stop. What is its angular acceleration? OA. 0.05% rad/s² B. 0.30 rad/s² OC. 0.60m rad/s² OD.-0.30 rad/s² E. -0.60 rad/s²

The 3.50 kg, 40.0-cm-diameter disk in (Figure 1) is spinning at 300 rpm. For help with math skills, you may want to review: Solving Algebraic Equations For general problem-solving tips and strategies for this topic, you may want to view a Video Tutor Solution of Nutcracker. Figure 3 1 of 1 Brake Part A How much friction force must the brake apply to the rim to bring the disk to a halt in 2.10 s ? Express your answer with the appropriate units. μà Value Submit Units Request Answer < Return to Assignment ? Provide Feedback

A solid disk, a circular hoop and a solid spherical ball (all made of the same material and with the same diameter) are released from rest and then roll down a slope. Which object reaches the bottom first? Select one: a. Solid spherical ball b. Solid disk c. Circular hoop d. None, they all reach the bottom at the same time

a. How fast in revolutions per minute must a centrifuge rotate if a particle 7.0 cm from the axis of rotation is to experience an acceleration of 100000 g's? b. Moment of inertia of a long (one-dimensional) uniform rod of mass M and length L2 through the center of the rod is equal to :a. 1/3 ML2 b. 1/6 ML2 c. 3/8 ML2 d. 2/5 ML2 e. 1/12 ML2