SOLUTION :i.i J 1., Free-Body Diagram: (a)+} 'fMB =0: -Ay(3.6 ft) -(1461b)(1.44 ft) -(631b)(3.24 ft) -(90 Ib)(6.24 ft) = 0 or Ay = 2711bl ~ Ay = -271.10 Ib (b) +) rMA = 0: By(3.6 it) -(1461b)(5.04 it) -(631b)(6.84 it) -(90 Ib)(9.84 it) = 0 or Bv = 570Ib t ~ By = 570.10 Ib PROPRIETARY MATERIAL. It> 2007 The McGraw-Hili Companies, .Inc. All rights reserved. No part of this Manual may be displayed, reproduced or distributed in anyform or by any means, without the prior written pelwission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. If you are a student using this Manual, you are using it without permi.~sion. 355 " PROPRIETARY MATERIAL. f:>2007 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced or distributed in anyfonn or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators pennitted byJ\.(cGraw-Hill for their individual course preparation. If you are a st!/dcnt using this Manual, .vou are using it without permission. 1ti5 SOLUTION Free-Body Diagram: .300"'M Equationsof equilibrium: +) rMA=0: + -x -(330 N)(0.25 m) + Bsina(0.3 m) + Bcosa(0.5 m) = 0 1:F = 0: Ax -Bsina = 0 (1) (2) Ay -(330 N) + Bcosa = 0 (3) (a) Substitution a = 0 into (1), (2), and (3) and solving for A and B: B = 165.000N, Ax = 0, Ay = 165.0N or A = 165.0N t. B = 165.0N t ~ (b) Substituting a = 9()° into (1), (2), and (3) and solving for A and B: B = 275.00N, Ax = 275.00N, (} = tan-l~ Ay = 330.00N = tan-I 330 = 50.1940 Ax m :. A = 430 N ~ 50.2°, B = 275 N -~ PROPRIETARY MATERIAL. ~ 2007 The McGraw-Hill Companies, Inc. All rights reserved. No part ofthis Manual may be displayed, reproduced or distributed in any form or by any means, without the prior written permission ofthe publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. If you are a student using this Manual, you are using it without permission. 372 PROPRIET AR YMA TERIAL @ 2007 The McGraw-HilI Companies, Inc. All rights reserved. No part of this Ma~ual maybe displayed, reproduced or distributed in any.form or by an}' means, without the prior written permission ofthe publisher, or used beyond the ,limited distribution to leachers and educators pennitted by McGraw-Hill for their individual course preparation. If you are a stltdent using this ,'vfanual,:you are using it witholt! pennis.\'ion. 373 r" 1d" ::1:1)0 1R' -, -'"" PROBLEM 4.25 ~J!!!;:; ,., A lever AD is hinged at C and is attachedto a control cable at A. If the lever is subjectedto a 60-lb vertical force at B, detennine (a) the tension in the cable, (b) the reaction at C. contin/ied PROPRIETARY ,'fATERIAL. @2007The McGraw-HilI Companies, Inc. All rights reserved. No part ofthis Mfnuul maybe displayed, reproduced or di.\"tributed in any.form or b_van}' means, ~ithout the prior written permi.l'sion ofthe publisher, or used beyond thr limited distribution to teachers and educutors permitted by,\1cGraw-Hill.for.t/~!r individual course preparation. If you are a student u.I'ing this Manua(, you are using it ~'ithout permi.l'sioll. PROPRIETARY ,WATERIAL. IQ 2007 The McGraw-Hili Companies. Inc. All rights reserved. No part ofthi~ Manual may be displayed, reproduced or distributed in anyform or b.y any means, lvithout the prior lI'rinen permission ofthe publisher, or used beyond the limited distlibution to teachet~ and educators pennitted b}. McGraw-Hill.for their individual course preparation.if.vou are a student using this Manual, you are using it ..'ithout permission. 389 SOLUTION (a) Free-Body Diagram: + EF = 0: -x E x =0 Ey -16.2 kN -5.4 kN -18 kN = 0 orE=39.6kNt~ Ey= 39.6 kN ME + (16.2 kN)(4.8 m) + (5.4 kN)(2.6 m) -(18 kN)(1.5 m) = 0 ME = -64.8 kN.m orME=64.8kN°m)~ PROPRIETARY MATERIAL. ~ 2007 The McGraw-HilI Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced or distributed in any fonn or by any means, without the prior written pennission of the publisher, or used beyond the limited distribution to teachers and educator.~permitted by McGraw-Hill for their individual course preparation. If you are a student using this Manual, you are using it without permission. 416 I~. !~ YJ PROBLEM 4.59 ~ and T A vertical load P is applied at endB ofrodBC. The constantof the spring is k and the spring is unstretchedwhen 0 = o. (a) Neglecting the weight of the rod, expressthe angle 0 correspondingto the equilibrium position in tenDSof P, k, and I. (b) Oetennine the value of 0 correspondingto equilibrium if P = 2kl. kx 2klsin~ 2 or 0 PROPRIETARY MATERIAL. () 2007 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced or distributed in anyfo1m or by any means, without the prior written pe1mission ofthe publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hillfor their individual course preparation./fyou are a student using this Manual, you are using it without permission. 428 SOLUTION Free-Body Diagram: ~ ,?=\~'"" ' -~ p / ~ 0.$'" '=., -~ ~ 2" ~~ Express all forces in tenDSof rectangularcomponents: rA = (2.4 m)i rB = (1.8 m)j AD = -(2.4 m)i + (0.3 m)j + (1.2m)k BE = -(1.8 m)i + (0.6 m)j -(0.9 m)k WA = -(440 N)j WB = -(440 N)j Then AD = TAD~(-2.4)2 -2.4i + 0.3j + l.2k 8 + (0.3)2+ (1.2)2 = -9T~ --'" T BE ~ -1BE- BE -'1' -.iDE -1.8i + O.6j -O.9k -6 ~(-1.8)2+(O.6)2+(-O.9f ---AnI T 7 1 + 9T~ .2 + T -ADJ 7 + ~TAJJk .3 T --AD"" '- Ir 7 PROPRIETARY MATERIAL 11::12007 The McGraw-Hill Companies,ffic. All rights reserved, No part of this Manual may be displayed, reproduced or distributed in anyform or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. If }'Ou are a student using this Manual, ,YOUare using it without permission. k"':;~~:'"' 522 PROBLEM 4.117 CONTINUED LMc = 0: r.4 x TAD+ rB x TBE+ rA x WA + rB x WB 0 or 0 Equating the coefficients of the unit vectorsto zero: .9.6 J: 9 T,W+-7-1.BE 5.47' 0 1848= 0 k or J:w 1890N ~ TSE 2610 N.. Forceequations: Cx 0, or C.,. 3920.0N 44ON 0, or c" 0, or Cv .76.657 N 279.99N c (3920N)i (76.7 N)j + (280 N)k PROPRIETARY l\1ATERIAL. '£' 2007 The McGraw-Hili Companies, Inc. All rights reserved. No pa!.t ofthis.iManual may beliisplayed. reproduced or di.l.tribllted in any {O/l11or by any means. without the prior written pe/lI1ission of the publisher. or ILsedbeyon~the /muted distribution to teachers and f,ducators permitted b..v,WcGraw-Hillfor thei,' individual course preparation. lfyou aloea .~tudentu.~ingthi.~lvlanu4/. .vou are IL'iingit without permi.~~ion. 523 /" ~'t ~ SOLUTION Free-Body Diagram: '1 28",. 10;~. -,",Co, 74;". /~/ ~. b -- -" Go ;If 1." ~ "! ~"t~~ ~O\¥\. ; ~. Expressforces in terns of their rectangularcomponents: -40i + 74 j -32k BG = ~BG--~ ~(-40)2 + (74)2 + (-32)2 -BG TBG= TBG-BG -BH TBH -TBHBii -30i+60j-60k -TBH ~(30)2 + (60)2 + (-6~)2 (-""4:5"1 20 . + ( 1. 2. 37 45 ~k) 45 2 = TBH 31 + 3J -3k ) P = -(751b)j AD }..AD = "AD" = 80i -60j ~(80Y + :-6~)2 = O.8i -O.6j PROPRIETARY MATERIAL. ~ 2007 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed. reproduced or distributed in anyform or by any means, Without the prior written permission of the publisher, or used beyond/he limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. If y'ou are a stu4ent u.~ingthis Manual. you are using it without permission. S78