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39. The angular position of a 0.36-m-diameter flywheel is given by rady 0=(2.0) ² Find 8 in radians at t= 2.0 s. (2) 40. The angular position of a 0.36-m-diameter flywheel is given by rad 0 = (2.0) ² Find the distance that a particle on the flywheel rim moves over the time interval from 1 = 2.0 s to t= 5.0 s. (2) 41. The angular position of a 0.36-m-diameter flywheel is given by rad = (2.0) ² . Find the instantaneous angular velocity at = 2.0 s 42. The angular position of a 0.36-m-diameter flywheel is given by = (2.0) ² . Find the average angular velocity in rad over the interval 1 = 2.0 s to 1 = 5.0 s. (3) (3)

44. Flywheel, which is simply large rotating disks have been suggested as a means of storing energy for solar-powered generating systems. Estimate the kinetic energy that can be stored in a 20 000 kg flywheel with diameter of 40 m. Assume it could hold together 10.5 rad/s (4) 00000000000

35. The horizontal arm illustrated in figure 9 below is composed of three parts, the upper arm (weight W₁ = 17 N), the lower arm (W2= 11 N) and the hand (W3 = 4.2 N). The drawing shows the center of gravity of each part, measured with respect to the shoulder joint. Find the center of gravity for the entire arm, relative to the shoulder joint. Upper arm Lower arm Hand 0.61 m - 0.38 m - 0.13 m Shoulder joint Upper arm Lower arm Hand W₁ Figure 9 Determine the center of gravity of the entire arm, relative to the shoulder. (4)