(5) The uniform rectangular plate is welded to the vertical shaft AB and the assembly is supported by cable CD, a thrust bearing at A, and a radial bearing at B. The weight of the plate is 100 N. A vertical 250 N force and a 120 N·m moment are applied on the assembly as shown. Determine the tension in cable CD and the magnitude of the reactions at the bearings. Ans: T = 650 N, A = 2170 N, B = 2790 N A 120 N-m 200 mm B 50mm 480 mm 200 mm 250 N D 400 mm

A 60-mm-diameter solid aluminum post is subjected to a horizontal force of V = 25 KN, a vertical force of P = 70 kN, and a concentrated torque of T = 3.25 kN-m, acting in the directions as shown in the Figure. If L = 90 mm. Determine the normal and shear stresses at (a) point Hand (b) point K. T "| P HK X L

A student presses a book between his hands, as the drawing indicates. The forces that he exerts on the front and back covers of the book are perpendicular to the book and are horizontal. The book weighs  25.8 N. The coefficient of static friction between his hands and the book is  0.326. To keep the book from falling, what is the magnitude of the minimum pressing force that each hand must exert?

A spring has a natural length of 10 feet, and when an 64lb weight is attached, the spring measures 13.2 feet. The weight is initially displaced 4 feet above equilibrium and given a downward velocity of 3 ft/sec. Find its displacement for t>0 if the medium resists the motion with a force of two Ibs for each ft/sec of velocity.

A helicopter flies over the arctic ice pack at a constant altitude, towing an airborne  147-kg laser sensor which measures the thickness of the ice (see the drawing). The helicopter and the sensor move only in the horizontal direction and have a horizontal acceleration of magnitude  2.54 m/s2. Ignoring air resistance, find the tension in the cable towing the sensor.

(2) The uniform door panel weighs 60 lb and is supported by hinges at A and B. A strut C is used to prevent the door from swinging when a horizontal force P = 50 lb is applied perpendicular to the door panel as shown. Determine the compression C in the strut and the magnitudes of the reaction forces normal to the hinge axis at A and B. Ans: C = 100 lb, An = 38.0 lb, B = 45.5 lb 40" 8" 48" 40" x 30" 8 8 A

The 0.50 lb ball is shot from the spring device shown. The spring has a stiffness k = 10 lb/in. and the four cords C and plate P keep the spring compressed 2 in. when no load is on the plate. The plate is pushed back 3 in. from its initial position. (Eigure 1) If it is then released from rest, determine the speed of the ball when it travels 23 in. up the smooth plane. Express your answer to three significant figure and include the appropriate units. HA Value ft/s v = 30

(3) The uniform rectangular plate is supported by two hinges at A and B and held in the horizontal position by cable EF as shown. The weight of the plate is 750 lb and a 300 lb force is applied at corner D of the plate. Determine (a) the tension T in cable EF, (b) the magnitude of the reaction force normal to the hinge axis at hinge B. Ans: (a) T 495 lb (b) B = 304 lb 300 lb 4 in. 30 in. 8 in. B 4 in. 25 in. 20 in. x

The second power of the distance from the inertia axis to an element of area is used to calculate the: Gravitational potential energy of an object. Second moment of area or moment of inertia of an object. Centroid of an object. O Area of an object.

A basket of flowers of mass 3 kg is placed on a flat grassy slope that makes an angle θ with the horizontal. The coefficient of static friction between the basket and the slope is 0.45 and the basket is on the point of slipping down the slope. Model the basket of flowers as a particle and the grassy slope as a plane. Take the magnitude of the acceleration due to gravity, g, to be 9.8 m s−2 Express the forces in component form, in terms of θ and unknown magnitudes where appropriate. Write down the equilibrium condition for the basket and hence show that tan θ = 0.45. Determine the angle, in degrees, that the slope makes with the horizontal.