物理常识.docx

Engineering Mechanics Test 1Engineering MechanicsResult & Statistics1.Solve the following equation forx,y, andz:xy+z= 1x+y+z= 1x+ 2y 2z= 5A.x= 1,y= 1,z= 1B.x= 5/3,y= 7/6,z= 1/2C.x= 2/3,y= 2/3,z= 1D.x= 1,y= 1,z= 1Answer:OptionALearn more problems on :General PrinciplesDiscuss about this problem :Discuss in Forum2.Express the forceF1in Cartesian vector form.A.F1= (200i- 200j+ 283k) lbB.F1= (200i+ 200j+ 283k) lbC.F1= (-200i+ 200j+ 565k) lbD.F1= (-200i+ 200j+ 283k) lbAnswer:OptionDLearn more problems on :Force VectorsDiscuss about this problem :Discuss in Forum3.Thegusset plate Gof a bridge joint is subjected to the two member forces atAandB. If the force atBis horizontal and the force atAis directed at= 30, determine the magnitude and direction of the resultant force.A.R = 458 N,= 97.5 CCWB.R = 252 N,= 82.5 CCWC.R = 252 N,= 97.5 CCWD.R = 458 N,= 82.5 CCWAnswer:OptionCLearn more problems on :Force VectorsDiscuss about this problem :Discuss in Forum4.Determine the magnitude and direction of the moment of the force of the movement if the force at A about point P.A.Mp = 1440 NmB.Mp = 600 NmC.Mp = 1440 NmD.Mp = 600 NmAnswer:OptionDLearn more problems on :Force System ResultantsDiscuss about this problem :Discuss in Forum5.A force and couple act on the pipe assembly. Replace this system by an equivalent single resultant force. Specify the location of the resultant force along theyaxis, measured fromA. The pipe lies in thex-yplane.A.R= 25k lb, y = -0.9 ftB.R= 25k lb, y = 0.9 ftC.R= 25k lb, y = 3.9 ftD.R= 25k lb, y = -3.9 ftAnswer:OptionALearn more problems on :Force System ResultantsDiscuss about this problem :Discuss in Forum6.Three parallel forces act on the rim of the tube. If it is required that the resultant forceFRof the system have a line of action that coincides with the centralzaxis, determine the magnitude ofFCand its locationon the rim. What is the magnitude of the resultant forceFR?A.Fc= 361 lb,= 56.3, R = 861 lbB.Fc= 500 lb,= 54.0, R = 1000 lbC.Fc= 500 lb,= 36.0, R = 1000 lbD.Fc= 361 lb,= 36.9, R = 861 lbAnswer:OptionALearn more problems on :Force System ResultantsDiscuss about this problem :Discuss in Forum7.Determine the direction (0180) of the 30-lb forceFso that the moment ofFabout point A has the minimum magnitude.A.= 36.9B.= 53.1C.= 127.0D.= 90.0Answer:OptionCLearn more problems on :Force System ResultantsDiscuss about this problem :Discuss in Forum8.The pole supports a 22-lb traffic light. Using Cartesian vectors, determine the moment of the weight of the traffic light about the base of the pole atA.A.MA= 216klb-ftB.MA= (-132i-229j-216k) lb-ftC.MA= (-229i+121j) lb-ftD.MA= (-132i+229j) lb-ftAnswer:OptionCLearn more problems on :Force System ResultantsDiscuss about this problem :Discuss in Forum9.The space truss is supported by a ball-and-socket joint atAand short links, two atCand one atD. Determine thex, y, zcomponents of reaction atAand the force in each link.A.Ax= -1.050 kN, Ay= 1.050 kN, Az= 0.800 kN, Cy= -1.050 kN, Cz= 0.600 kN, Dx= 1.050 kNB.Ax= -1.400 kN, Ay= 1.400 kN, Az= 0.800 kN, Cy= -1.400 kN, Cz= 0.600 kN, Dx= 1.400 kNC.Ax= -2.49 kN, Ay= 1.867 kN, Az= 0.800 kN, Cy= -2.49 kN, Cz= 0.600 kN, Dx= 2.49 kND.Ax= -1.867 kN, Ay= 1.867 kN, Az= 0.800 kN, Cy= -1.867 kN, Cz= 0.600 kN, Dx= 1.867 kNAnswer:OptionDLearn more problems on :Equilibrium of a Rigid BodyDiscuss about this problem :Discuss in Forum10.Determine the inertia of the parabolic area about thexaxis.A.Ix= 11,430 in.4B.Ix= 32,800 in.4C.Ix= 13,330 in.4D.Ix= 21,300 in.4Answer:OptionALearn more problems on :Moments of InertiaDiscuss about this problem :Discuss in Forum11.For a short time the position of a roller-coaster car along its path is defined by the equationsr= 25 m,= (0.3t) rad, andz= (-8 cos) m, wheretis measured in seconds, Determine the magnitudes of the cars velocity and acceleration whent= 4s.A.v = 7.83 m/s, a = 2.27 m/s2B.v = 9.74 m/s, a = 2.51 m/s2C.v = 7.50 m/s, a = 2.25 m/s2D.v = 5.26 m/s, a = 1.989 m/s2Answer:OptionALearn more problems on :Kinematics of Particle (KOP)Discuss about this problem :Discuss in Forum12.Determine the acceleration of blockAwhen the system is released. The coefficient of friction and the weight of each block are indicated in the figure. Neglect the mass of the pulleys and cords.A.aA= 7.50 ft/s2Up the slopeB.aA= 7.50 ft/s2Down the slopeC.aA= 4.28 ft/s2Up the slopeD.aA= 4.28 ft/s2Down the slopeAnswer:OptionDLearn more problems on :KOP: Force and AccelerationDiscuss about this problem :Discuss in Forum13.A toboggan and rider, having a total mass of 150 kg, enter horizontally tangent to a 90 circular curve with a velocityVAand the angleof descent, measured from the horizontal in a verticalxzplane, at which the toboggan exits atB. Neglect friction in the calculation. The radiusrBequals 57 m.A.vB= 21.9 m/s,= 20.9B.vB= 23.4 m/s,= 29.0C.vB= 20.7 m/s,= 8.84D.vB= 20.3 m/s,= 7.37Answer:OptionALearn more problems on :KOP: Impulse and MomentumDiscuss about this problem :Discuss in Forum14.The oil pumping unit consists of a walking beamAB, connecting rodBC, and crankCD. If the crank rotates at a constant rate of 6 rad/s, determine the speed of the rod hangerHat the instant shown.A.vH= 17.76 ft/sB.vH= 16.20 ft/sC.vH= 18.00 ft/sD.vH= 16.42 ft/sAnswer:OptionCLearn more problems on :Planar Kinematics of a Rigid Body (PKRB)Discuss about this problem :Discuss in Forum15.The dragster has a mass of 1.3 Mg and a center of mass at G. If a braking parachute is attached at C and provides a horizontal braking force FD, determine the maximum deceleration the dragster can have upon releasing the parachute without tipping the dragster over backwards (i.e., the normal force under the wheels and assume that the engine is disengaged so that the wheels are freely rolling.A.a = 16.35 m/s2B.a = 8.46 m/s2C.a = 2.75 m/s2D.a = 35.0 m/s2Answer:OptionALearn more problems on :PKRB: Force and AnimationDiscuss about this problem :Discuss in Forum16.The disk has a mass of 20 kg and is originally spinning at the end of the massless strut with an angular velocity of= 60 rad/s. If it is then placed against the wall, for whichA= 0.3, determine the time required for the motion to stop. What is the force in strutBCduring this time?A.t = 3.11 s, FBC= 193.1 NB.t = 2.65 s, FBC= 227 NC.t = 5.30 s, FBC= 227 ND.t = 6.21 s, FBC= 193.1 NAnswer:OptionALearn more problems on :PKRB: Force and AnimationDiscuss about this problem :Discuss in Forum17.The uniform slender rod has a mass of 5 kg. Determine the magnitude of the reaction at the pinOwhen the cord atAis cut and= 90A.O = 42.0 NB.O = 91.1 NC.O = 122.6 ND.O = 67.4 NAnswer:OptionBLearn more problems on :PKRB: Work and EnergyDiscuss about this problem :Discuss in Forum18.The spool of cable, originally at rest, has a mass of 200 kg and a radius of gyration ofkG= 325 mm. If the spool rests on two small rollersAandBand a constant horizontal force ofP= 400 N is applied to the end of the cable, compute the angular velocity of the spool when 8 m of cable has been unraveled. Neglect friction and the mass of the rollers and unraveled cable.A.= 10.00 rad/sB.= 12.31 rad/sC.= 17.41 rad/sD.= 40.0 rad/sAnswer:OptionCLearn more problems on :PKRB: Work and EnergyDiscuss about this problem :Discuss in Forum19.A chain that has a negligible mass is draped over a sprocket which has a mass of 2 kg and a radius of gyration ofkO= 50 mm. If the 4-kg blockAis released from rest in the position shown,s= 1 m, determine the angular vel