1)A block of mass m1 = 8.00 kg and a block of mass m2 = 12.0 kgare connected by a massless string over a pulley in the shape of asolid disk having radius R = 0.350 m and mass M = 12.0 kg. Thecoefficient of kinetic friction between block m1 and the table is0.27. a) Draw force diagrams of both blocks and of the pulley. b)Determine the acceleration of the two blocks. c) Determine thetensions ?1 and ?2 in the string on both sides of the pulley. d)How would the answer for ?1 and ?2 change is the pulley weremassless?

2)During a certain time interval the angular position of aswinging door is described by θ = 5.3 + 7.1t + 4.5t 2 , where θ isin radians and t is in seconds. Determine (a) the angular positionat t = 2 sec, (b) angular speed at t = 2 sec, and (c) angularacceleration of the door at t = 2 sec.

3)A figure skater is spinning with an angular velocity of 16rad/s. She then comes to a stop over a brief period of time. Duringthis time, her angular displacement is 5 rev. Determine (a) heraverage angular acceleration and (b) the time during which shecomes to rest

4)A disk 6.00 cm in radius rotates at a constant rate of 98.0rev/s about its central axis. (a) Determine the tangential speed ata point 4.00 cm from its center. (b) Determine the centripetalacceleration of a point on the rim.

5)Two girls ?1 = 21.0 kg and ?2 = 29.0 kg are standing 1.00 maway from the center of a rotation platform (Figure (a)), and theplatform rotates at angular speed of 3.00 rad/s. Then both girlsbegin to walk towards the edge of the platform. If the radius ofthe platform is 2.00 m, what is the final angular speed of thesystem, when the girls reach the platform’s edge (Figure (b))?Model the platform as a uniform disk of mass M =350 kg, and thegirls as point masses. The moment of inertia of a disk of mass Mand radius R is 2 2 1 I disk = MR .