The crane below is on level ground. The x axis is through the contact points of the rearmost wheels with the ground, the y axis is parallel to the front-to-back centerline, and the z axis is vertical as shown. The bed (platform) of the crane is 3 ft above the ground. For practical purposes the pivot point of the bottom of the boom can be considered in the bed of the crane and 6 ft from the center of the cab. The center of the cab is on the centerline 15 ft forward (to the left) of the rearmost axle. The 50-ft boom makes an angle of 60° with the bed of the crane in a vertical plane, and the cab and boom are swiveled 45° horizontally from the fore and aft centerline of the truck bed. The distance between the contact points of the rear wheels is considered to be 8 ft. Determine the turning moment of the 4000-lb load about the x axis.
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