Chapter 4, Problem 17FP

Determine the moment of the force F=9i+18jlb about point O by the following methods: (a) vector method using rF; (b) scalar method using rectangular components of F; and (c) scalar method using components of F that are parallel and perpendicular to the line OA.

The trapdoor is held in the horizontal plane by two wires. Replace the forces in the wires with an equivalent force R that passes through point A, and determine the y-coordinate of point A.

The force-couple system consists of the force R=250i+360j400kN and the couple-vector CR=1200i+750j+560kNm. Determine the equivalent wrench and find the coordinates of the point where the axis of the wrench crosses the xy-plane.

The force F of magnitude 200 N is perpendicular to the plane ABC. Determine the magnitude of its moment about the x-axis.

The tensions in the cables supporting the pole are T1=T2=T3=60kN. Replace the cable tensions with an equivalent force-couple system with the force acting at O. Express your answer in vector form.

6

Calculate the magnitude of the moment about the base point O of the 600-N force. 2 m 40° 600 N 4 m

A set of forces acts on the assembly as shown. Note that the 120-N force is along the z-axis. Compute for the magnitude of the moment of the forces about point A in N-m?

Find the x-component the resultant of two forces: A= 150N, acting 30 degrees to left of the y-axis, and B=100N, acting 40 degrees below the x-axis.