Chapter 13, Problem 20P

The 300-kg bar B, originally at rest, is being towed over a series of small rollers. Determine 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 = (0.47²) m/s, where t is in seconds (0 <= t<= 6 s). How far does the bar move in 5s? Neglect the mass of the cable, pulley, and the rollers. M B

2. The 2-kg pendulum bob moves in the vertical plane with a velocity of 8 m/s when 0=0°. Determine the initial tension in the cord and at the instant the bob reaches 0=35°. Neglect the size of the bob. 2 m

The conveyor belt delivers each 12-kg crate to the ramp at A such that the crate’s speed is vA = 2.5 m>s,directed down along the ramp. If the coefficient of kinetic friction between each crate and the ramp is mk = 0.3,determine the smallest incline u of the ramp so that the crates will slide off and fall into the cart

The 56.28 kg crate is hoisted up the 0 = 27° incline by the pulley system and motor M. If the crate starts from rest and, by constant acceleration, attains a speed of 8.17 m/s after traveling 7.84 m along the plane, determine the supplied power to the motor if the crate has moved 8 m and the coefficient of kinetic friction between the plane and the crate is Hk = 0.3. Neglect friction along the plane. The motor has an efficiency of 0.691. M

The cars of an amusement park ride have a speed va = 17 m/s at A and a speed vg = 10 m/s at B. If a 87-kg rider sits on a spring scale (which registers the normal force exerted on it), determine the scale readings as the car passes points A and B. Assume that the person's arms and legs do not support appreciable force. UB 47 m B VA 24 m A

The 150-lb car of an amusement partk ride is connected to a rotating telescopic boom. When r = 15 ft, the car is moving on a horizontal circular path with a speed of 30 ft/s. If the boom is shortened at a rate of 3 ft/s, determine the speed of the car when r = 10 ft. Also, find the work done by the axial for F along the boom. Neglect the size of the car and the mass of the boom.

The spring is not stretched or compressed when “s=0.8m" and the 11 kg block which is subjected to a force of 105 N has a speed of 5.5 m/s down the smooth plane. Using "THE PRINCIPLE OF WORK AND ENERGY", find the distance "s" when the block STOPS. k = 200 N/m 5 m/s F = 100 N 30°

A freight elevator, including its load, has a mass of 1.1 Mg. It is prevented from rotating due to the track and wheels mounted along its sides. If the motor M develops a constant tension T = 6.9 kN in its attached cable, determine the velocity of the elevator when it has moved upward 7.2 m starting from rest. Neglect the mass of the pulleys and cables.

If the motor draws in the cable with an acceleration of 3 m/s^2, determine the reactions at the supports A and B. The beam has a uniform mass of 30 kg/m, and the crate has a mass of 200 kg. Neglect the mass of the motor and pulleys.