2.5 3-D Rectangular Coordinate Systems
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Figure 2.47: Example 2.21 ([2], pp. 68)
Figure 2.48: Solution to example 2.21 onto the z-axis and the x-y plane. Then the force in the x-y plane is further decomposed into the x- and y- axes, respectively. P = P cos 30 cos 20i + P cos 30 sin 20j + P sin 30k = 26.0i + 9.48j + 16k N The directional angle is determined by eq. 2.24. θx = acos P·i = 34.5◦ P P·j θy = acos P = 72.8◦ θz = acos P·k = 60◦ P Example 2.22 ([1], Prob. 2/112) The rectangular plate is supported by hinges along its side BC and by the cable AE. If the cable tension is 300 N, determine the projection onto line BC of the force exerted on the plate by the cable. Chulalongkorn University
Phongsaen PITAKWATCHARA