374 Static Equilibrium and ElasticityP12.60When it is on the verge of slipping, the cylinder is in equilibrium.Fx∑=0:fnns121==µands22=Fy∑=Pn f Fg++=τ∑=Pf f=+As Pgrows so do f1and f2Therefore, since s=12,fn112=andfnn22124FIG. P12.60thenPnnFg++ =114(1)andPn=+=11134(2)SoFg+=541becomesPPFg+FHGIKJ=5443or83PFg=Therefore, g=38P12.61(a)FkL=∆af, Young’s modulus is YFLALFALLii∆∆Thus, YkLAi=and kYALi=(b)WFdxkx dxYALxdxYALLLLiLi=−−==zzz00022∆∆∆∆P12.62(a)Take both balls together. Their weight is 3.33 Nand their CG is at their contact point.Fx∑=0: +−=310Fy∑=+−=P23330. NP2=NA∑=−+−+°PR PRR R32450.cos.N++°=PR R1500cos.Substituting,−+°°=°=°PRRRPRP11113112 450 02167..cos.cos..cos.cos...N NNsoNafFgP1P2P33.33 NFIG. P12.62(a)(b)Take the upper ball. The lines of action of its weight, of
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This note was uploaded on 12/14/2011 for the course PHY 203 taught by Professor Staff during the Fall '11 term at Indiana State University .