A cart moving right on a frictionless track collides with a 3.0 kg cart moving left at 2.0 * m/s The 1.0 kg cart has a fina speed of 4.0 * m/s to the left.

The space between two 15-in.-long concentric cylinders is filled with glycerin (viscosity = 8.5 × 10-3 lb·s/ft2). the inner cylinder has a radius of 1 in. and the gap width between cylinders is 0.1 in. determine (a) the torque and (b) the power required to rotate the inner cylinder at 180 rev/min. the outer cylinder is fixed. assume the velocity distribution in the gap to be linear.