1) Two objects (50.0 and 24.0 kg) are connected by a massless string that passes over a massless, frictionless pulley. The pulley hangs from the ceiling. Find (a) the acceleration of the objects and (b) the tension in the string.
2) Two blocks are sliding to the right across a horizontal surface, In Case A the mass of each block is 4.3 kg. In Case B the mass of block 1 (the block behind) is 8.6 kg, and the mass of block 2 is 4.3 kg. No frictional force acts on block 1 in either Case A or Case B. However, a kinetic frictional force of 8.4 N does act on block 2 in both cases and opposes the motion. For both Case A and Case B determine (a) the magnitude of the forces with which the blocks push against each other and (b) the magnitude of the acceleration of the blocks.
2) Two blocks are sliding to the right across a horizontal surface, In Case A the mass of each block is 4.3 kg. In Case B the mass of block 1 (the block behind) is 8.6 kg, and the mass of block 2 is 4.3 kg. No frictional force acts on block 1 in either Case A or Case B. However, a kinetic frictional force of 8.4 N does act on block 2 in both cases and opposes the motion. For both Case A and Case B determine (a) the magnitude of the forces with which the blocks push against each other and (b) the magnitude of the acceleration of the blocks.
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1) acceleration a = (m1 - m2) g / m1+m2 = (50 -24) 9.8 / 74 = 3.44 m/sec^2
tension T = 2 m1m2g / m1+m2 = 2x50x24x9.8 / 74 = 317.8 N
2) contact force fc = 8.4x8.6 / 12.9 = 5.6 N(for first block) and fc = 8.4x4.3 / 12.9 = 2.8 N
and acceleration a = 8.4 / 12.9 = 0.651 m/sec^2.
tension T = 2 m1m2g / m1+m2 = 2x50x24x9.8 / 74 = 317.8 N
2) contact force fc = 8.4x8.6 / 12.9 = 5.6 N(for first block) and fc = 8.4x4.3 / 12.9 = 2.8 N
and acceleration a = 8.4 / 12.9 = 0.651 m/sec^2.