Question

Question I.5 Figure 1.5 shows a frame with loads at A and D. Select the closest value for the magnitude of the total reaction at B. Assume the weight of the frame is zero. 40 kN VE 96.2 kN (a) (Ь -40 kN 5 m (c) -87.5 kN 30 kN (d) 57 kN 4m ao 1 m (e) 50 kN Figure L.5 Low mass frame Question I.6 In the shear and bending moment equations for beams, which of the following statements true? (a) Bending moment is the derivative shear M dV/dx (b) Shear is the derivative of the bending moment V dM/dx. (c) Bending moment is always maximum when shear is maximum (d) Shear is maximum when bending moment is zero. (e) The value f the bending moment is the slope of the shear force diagram. Question I.7 For the truss with three extemal forces shown in Figure l.7, determine the number of zero force members. F (а) 4 (b) 1 (c) 2 (d) 3 (e) There are no zero force members. Pin Roller Figure I.7 Truss with three external forces Question .8 Truss ABC in Figure I.8 is changed by decreasing its height from H to 0.9H The width, W and load P are kept the same. Which one of the following statements true for the revised truss (a) The forces in all the members have increased. (b) The forces in all the members have decreased. (c) The diagonal member forces increase but the horizontal member force decreases. because the (d) aln metrical structure is still s w Fcy (e) The diagonal member forces decrease but the Figure L.8 Three member truss horizontal member force increases. Question I.9 A block of mass by a massless pulley, connects the block The two-block system in Figure I.9 is on the point of slipping. Which of the expressions represents the value of the coefficient of static friction, u, between the block and plane? slides on an inclined plane with a slope of 30 degrees massless rope, guided a second block of mass M/10, which is hanging freely. (a) = tan (30) (b) Htan(30) 10/cos(30) (c) utan(30) +1/cos(30) 30 (d) 0.1*tan30) (e) H tan (30)+ 0.1/cos(30) M/10 9 Mass on slope with friction Figure Question I.10 The shape shown in Figure 10 has its centroidal axis Y-Y 25.6mm from the left hand edge. uate the secu onent of area about Y-Y th Noto r significant figures. answer is given to diameter is given by TTR 14. The second moment of area of a circle about its own 50 mm 521000 mm (a) T-25.6mm 50mm (b) = 491 mm 520000 mm (c) =490000 mm 2420 mm (d) (e) 5.5 mm Figure I.10 Square with circular hole Part l: 10 Multiple Choice questions (Total Marks = 40) Question I.1 A beam is shown in Figure I.1. Select the correct shape for the shear force diagram. w.kN/m L2- I 1 Figure I.1 Beam with distributed load and a point load (a) (b) (d (c) (e) None of the Shear force diagrams match this beam. Question I.2 Find the magnitude of the resultant of the three forces shown in Figure 1.2 and select the closest answer (a) 23 N (b) 13.6 N (c) 38.3 N 30 N 20 N (d) 40.6 N (e) 70.5 N 20 N Figure I.2 Three force vectors Question 1.3 of the centroidal axis from O. For the dimensions in Figure In Figure I.3, represents the distance I.3, select the closest value for from the list of options. 18 All dimensions in mm (a) 19.3 mm (b) 39.0 mm (c) 17.2 mm 50 (d) 9.0 mm (e) 1236 mm2 60 Figure 1.3 Centroid of L shaped area Question 1.4 A roller coaster car of mass M, travels along a frictionless track. At the start it is at rest at a height above the datum. Then it travels down a slope, does a 360 degree loop, the top of which is above the datum. Which one of the following statements describes the energy of the car as of 60 at 50 passes the top of the loop? Neglect air resistance. (a) The total energy of the car has reduced by 10M . (b) Both the potential energy and the total energy of the car increase. (c) The kinetic energy of the car is instantaneously zero. (d) The kinetic energy decreases by 10Mg and the potential energy increases by that amount. (e) The kinetic energy increases by 10Mg and the potential energy decreases.

Answer 1

By 40KN 40kN 0=wz 30(5) 5m ylu) t405) 0 -) 30 k -87.5 EN Rexultonl fora at B 40 -1(875) Ans (a] 96.2 KN moment is the Bending hequned points two vdvm dn V = .Ans NO membi Zeno 3 Ans (d 1.8 in detormin Shuchures Changes from H to 09H) duchped Shers au in members. n forces in mimbes a not changlad (d] The foices Yemon unchonged becawe shuchu Anst

Ayomthical 1s shll HN N-M CoS30 A. 30 ID Tan 30 0.I coS300 .Ans 50mm .10 X-25 hAT Sbmm S0. 501es)(50) + (60256-15 2 o43 46x10 mm 5.5m R 5mm (Tnden TT 5) IAx 32221745 mm (25. L 56-25) 521733.333 mm +50(50) 50 (Fry) Yecl --(3222|. 745) + 5217 33.333 413C00 mm H89511.588 m . Ans

pant 1 1-1) Shear for ce 1 And 1.9 F, 20+ 2D C0550 t 30Cos 130 0 20N Fy= 13.572 N 20N 20 SinD20 Sin s+ 30SinB 30-64.2 N 38.302N [d] Ans FJE E40.636 N 1.3 AF 13(50-5) = 756 mm -9mm 50mm A, =60(8)= 4mm =Gb =3omm 2 60 mm 756 (4)-t 4S0 (20) ΣΑ,% 56 +480 ZAi mm R55 mm Ans c]