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When a wood shelf of mass 6.6 kg is fastened inside a slot in a vertical support as shown in Fig. 12–76, the support exerts a torque on the shell. (a) Draw a free-body diagram for the shelf, assuming three vertical forces (two exerted by the support slot—explain why). Then calculate (b) the magnitudes of the three forces and (c) the torque exerted by the support (about the left end of the shelf).
FIGURE 12–76
Problem 61.
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