KOP: Force and Acceleration - General Questions (2)

Determine the acceleration of block A when the system is released. The coefficient of friction and the weight of each block are indicated in the figure. Neglect the mass of the pulleys and cords.

A boy twirls a 15-lb bucket of water in a vertical circle. If the radius of curvature of the path is 4 ft, determine the minimum speed the bucket must have when it is overhead at A so no water spills out.

The 2-kg shaft CA passes through a smooth journal bearing at B. Initially, the springs, which are coiled loosely around the shaft, are unstretched when no force is applied to the shaft. In this position s = sª = 250 and the shaft is originally at rest. If a horizontal force of F = 5 kN is applied, determine the speed of the shaft at the instant s = 50 mm, sª = 450 mm. The ends of the springs are attached to the bearing at B and the caps at C and A.

A ball having a mass of 2 kg slides without friction within a vertical circular slot. If it is released from rest when  = 10°, determine the force it exerts on the slot when it arrives at points A and B.

A 1.5-lb brick is released from rest A and slides down the inclined roof. If the coefficient of friction between the roof and the brick is  = 0.3, determine the speed at which the brick strikes the gutter G.

The 300-kg bar B, originally at rest, is being towed over a series of small rollers. Computer the force in the cable when t = 5s, if the motor M is drawing in the cable for a short time at a rate of v = (0.4t²) m/s, where t is in seconds (0  t 6 s). How far does the bar move in 5 s? Neglect the mass of the cable, pulley P, and the rollers.

The 30-lb crate is being hoisted upward with a constant acceleration of 6 ft/s². If the uniform beam AB has a weight of 200 lb, determine the components of reaction at A. Neglect the size and mass of the pulley at B.

Rod OA rotates counterclockwise with a constant angular rate of  = 5 rad/s. The double collar B is pin-connected together such that one collar slides over the rotating rod and the other slides over the horizontal curved rod, of which the shape is a limacon described by the equation r - 1.5(2 - cos ) ft. If both collars weigh 0.75 lb, determine the normal force which the curved path exerts on one of the collars, and the force that OA exerts on the other collar at the instant  = 90°.