Q/1Determine the magnitude FS of the tensile spring force in order that the resultant ofFS and F is a vertical force. Determine the magnitude R of this vertical resultant force.Ams: FS 60 IbR 103.9 IbQ/2Determine the magnitude of the resultant force and its direction, measuredcounterclockwise from the positive x-axis.Ans: R 997.75 Nθ 134.8ᴼQ/3Determine the angle θ for connecting member A to the plate so that the resultantforce of FA and FB is directed horizontally to the right. Also, what is the magnitude of theresultant force?Ans: θ 54.9ᴼ, R 10.4 kN

Q/4Four forces are exerted on the eyebolt as shown. If the net effect on the bolt is a direct pullof 600 Ib in the y-direction, determine the necessary values of T and θ.Ans: T 204 Ib, θ 21.7ᴼQ/5The vertical force F acts downward at A o the two membered frame. Determine themagnitudes of the two components of F directed along the axes of AB and AC. SetF 500 N.Ans: FAB 448 NFAC 366 N

Q/6The force exerted by the plunger of cylinder AB on the boor is 40 N directed alongthe line AB, and this force tends to keep the door closed. Compute the moment of thisforce about the hinge O. what force FC normal to the plane of the door must the door stopat c exert on the door so that the combined moment about O of the two forces is zero?Ans:MO 7.03 N.mFC 8.53 NQ/7Calculate the moment MO of the 250 N force about the base point O of the robot.Ans: MO 189.6 N.m CCW

Q/8The piston, connecting rod, and crankshaft of a diesel engine are shown in thefigure. The crank throw OA is half the stroke of 8 in., and the length AB of the rod is 14in. for the position indicated, the rod is under a compression along AB of 3550 Ib.determine the moment M of this force about the crankshaft axis O.Ans. MO 13670 Ib.inQ/9Each propeller of the twin-screw ship develops a full-speed thrust of 300 kN. Inmaneuvering the ship, one propeller is turning full speed ahead and the other full speed inreverse. What thrust p must each tug exert on the ship to counteract the turning effect ofthe ship's propellers?Ans.P 51.4 kN

Q/10The system consisting of the bar OA, two identical pulleys, and a section of thintape is subjected to the two 180 N tensile forces shown in the figure. Determine theequivalent force-couple system at point O.Ans.MO 21700 N.mmQ/11The gear and attached V-belt pulley are turning counterclockwise and are subjectedto the tooth load of 1600 N and the 800 N and 450 N tensions in the V-belt. Represent theaction of these three forces by a resultant force R at O and a couple of magnitude M. is theunit slowing down or speeding up?Ans.R 1908 NMO 127.5 N.m CCW

Q/12Replace the three forces which act on the bent bar by a force-couple system at thesupport point A.Ans.R 3036 IbMA 18190 Ib-ft CWQ/13Reduce the given loading system to a force-couple system at point A. thendetermine the distance x to the right of point A at which the resultant of the three forcesacts.Ans.R 80 Ib downMA 1240 CWx 15.5 in.Q/13The elements of a heavy-duty fluid valve are shown in the figure. When the memberOB rotates clockwise about the fixed pivot O under the action of the force P, the element Sslides freely upward in its slot, releasing the flow. If an internal tensional spring exerts amoment M – 20 N.m as shown, determine the force p required to open the valve. Neglectall friction.Ans.P 111.1 N

Q/14The cords BCA and CD can each support a maximum load of 100 Ib. determine themaximum weight of the crate that can be hoisted at constant velocity, and the angle θ forequilibrium.Ans.θ 78.7ᴼW 51 IbQ/15Determine the magnitude and angle θ of F so that the particle is in equilibrium.Ans.θ 49.8ᴼF 11 kN

Q/16If blocks D and F weight 5 N each, determine the weight of block E if the sags 0.3m. Neglect the size of the pulleys.Ans.W 6 IbQ/17A scale is constructed with a 1.2 m long cord and the 50 N block D. the cord is fixedto a pin at A and passes over two small pulleys. Determine the weight of the suspendedblock B if the system is in equilibrium when s 1.45 m.Ans.W 18.3 Ib

Q/18What horizontal force p must a worker exert on the rope to position the 50 kg cratedirectly over the trailer?Ans.P 126.6 NQ/19The man pushes the lawn mower at a steady speed with a force P that is parallel tothe incline. The mass of the mower with attached grass bag is 50 kg with mass center at G.if θ 15ᴼ, determine the normal forces NB and NC under each pair of wheels B and C.neglect friction. Compare with the normal forces for the conditions of θ 0 and P 0.Ans.NB 214 N, NC 260 NWith θ P 0 :NB 350 N, NC 140.1 N

Q/20Determine the force in each member of the loaded truss. Make use of the symmetryof the truss and of the loading.Ans.AB DE 96 kN CAH EG 75 kN TBC CD 75 kN CBH CG DF 60 kN TCH CF 49 kN CGH FG 112.5 kN TQ/21The equiangular truss is loaded and supported as shown. Determine the forces in allmembers in terms of the horizontal load L.Ans.AB BC L T, AG EF L CDE CD L/2 T, BF DF BD 0

Q/22Determine the forces in members AB, CG, and DE of the loaded truss.Ans.AB 7/2 L CCG L CDE 7/2 L CQ/23The tower for a transmission line is modeled by the truss shown. The crossedmembers in the center sections of the truss may be assumed to be capable of supportingtension only. For the loads of 1.8 kN applied in the vertical plane, compute the forcesinduced in members AB, DB, and CD.Ans.AB 3.89 kN CDB 0CD 0.932 kN C

Q/24Determine the force in each member of the truss and state if the members are intension or compression.Ans.BC 3 kN C, BA 8 kN CAC 1.46 kN C, AF 4.17 kN TCD 4.17 kN C, CF 3.12 kN CED 13.1 kN C, DF 5.21 kN TQ/25Determine the force in member DG of the loaded truss. Ans. DG L T

Q/26The truss is composed of equilateral triangles of side a and is supported and loadedas shown. Determine the force in members DC and CG.Ans. BC CG L/3 TQ/27Compute the force in member GM of the loaded truss.Ans. GM 0

Q/28A design model for a transmission-line tower is shown in the figure. Members GH,FFG, OP , and NO are insulate cables; all other members are steel bars. For the loadingshown compute the forces in members FI, FJ, EJ, EK, and ER.Ans.FI ER 0, FJ 7.81 kN TEJ 3.61 kN C, EK 22.4 kN CQ/29Determine the magnitudes of all pin reactions for the frame loaded as shown.Ans. A 512 N, B D 1013 N

Q/30Determine the reaction at the roller F for the frame loaded as shown.Ans. F 800 NQ/31A small bolt cutter operated by hand for cutting small bolts and rods is shown in thesketch. For a hand grip P 150 N, determine the force Q developed by each jaw on therod to be cut.Ans. Q 2.7 kNQ/32The unstretched length of spring EF is 300 mm. determine the magnitude of the pinreaction at O.Ans. OX 1512 NOY 0

Q/33Determinne the x- and y- components of all forces acting on each member of theloaded frame for the conditions (a) θ 0 and (b) θ 30ᴼ. Force P is applied to the midpointof member BC.Ans.Q/34The 85 Ib force P is applied to the 200 Ib crate, which is stationary before is applied.Determine the magnitude and direction of the friction force F exerted by the horizontalsurface on the crate.Ans. F 85 Ib to the leftQ/35The coefficients of static and kinetic friction between the 100 kg block and theinclined plane are 0.3 and 0.2, respectively. Determine (a) the frictio force F acting on theblock when p is applied with a magnitude of 200 N to the block at rest, (b) the force Prequired to initiate motion up the incline from rest, and (c) the friction force F acting onthe block if P 600 N.Ans.(a) F 66 N up(b) P 516 N(c) 148.5 N

Q/36Determine the range of weights W for which the 100Ib block is in equilibrium. Allwheels and pulleys have negligible friction.Ans.3.05 Ib W 31.7 IbQ/37The force P is applied to (a) the 60 Ib block and (b) the 100 Ib blick. For each case,determine the magnitude of p required to initiate motion.Ans.P(a) P(b) 19.2 IbQ/38The three bars have a weight of WA 20 N, WB 40 N and WC 60 N,respectively. If the coefficients of static friction at the surfaces of contact are as shown,determine the smallest horizontal force P needed to move block A.Ans.P 63.5 Ib