Description : Bending stress will be least at the extreme fibres for (a) Maximum area of cross section (b) Maximum moment of inertia (c) Maximum section modulus (d) None
Last Answer : (c) Maximum section modulus
Description : The slenderness ratio is the ratio of (a) Length of column to least radius of gyration (b) Moment of inertia to area of cross-section (c) Area of cross-section to moment of inertia (d) Least radius of gyration to length of the column
Last Answer : (a) Length of column to least radius of gyration
Description : Which of the following relations is used to represent theorem of perpendicular axes? (H = Vertical axis, I = Moment of inertia and K = Radius of gyration) a. IPQ = Ixx + AH2 b. IPQ = Ixx + Ak2 c. Izz = Ixx + Iyy d. Izz + Ixx + Iyy = 0
Last Answer : c. Izz = Ixx + Iyy
Description : The product of the tangential force acting on the shaft and radius of shaft known as (a) Torsional rigidity (b) Flexural rigidity (c) Bending moment (d) Twisting moment
Last Answer : (d) Twisting moment
Description : A circular shaft subjected to torsion undergoes a twist of 10in a length of 120 cm. If the maximum shear stress induced is limited to 1000 kg/cm2and if modulus of rigidity G = 0.8 x 106then the radius of the shaft should be (a) p/8 (b) p/27 (c) 18/p (d) 27/p
Last Answer : (d) 27/p
Description : A column is said to be a short column, when (a) its length is very small (b) its cross-sectional area is small (c) the ratio of its length to the least radhis of gyration is less than 80 (d) the ratio of its length to the least radius of gyration is more than 80
Last Answer : (c) the ratio of its length to the least radhis of gyration is less than 80
Description : If M, I, R, E, F, and Y are the bending moment, moment of inertia, radius of curvature, modulus of elasticity stress and the depth of the neutral axis at section, then (A) M/I = R/E = F/Y (B) I/M = R/E = F/Y (C) M/I = E/R = E/Y (D) M/I = E/R = Y/F
Last Answer : (C) M/I = E/R = E/Y
Description : Along with the expression define radius of gyration and sectional modulus.
Last Answer : Radius of gyration (K): The radius of gyration of a given area about any axis is the distance from the given axis at which the area is assumed to be concentrated without changing the MI about the given ... It is the ratio of moment of inertia to the distance of extreme fiber from neutral axis.
Description : Pick up the incorrect statement from the following: The torsional resistance of a shaft is directly proportional to (A) Modulus of rigidity (B) Angle of twist (C) Reciprocal of the length of the shaft (D) Moment of inertia of the shaft section
Last Answer : (D) Moment of inertia of the shaft section
Description : Modulus of rigidity is (a)Tensile stress / Tensile strain (a)Shear stress / Shear strain (a)Tensile stress / Shear strain (a)Shear stress / Tensile strain
Last Answer : (a)Shear stress / Shear strain
Description : is the pre-stressed force applied to the tendon of a rectangular pre-stressed beam whose area of cross section is and sectional modulus is . The maximum stress in the beam, subjected to a maximum bending moment , is (A) f = (P/A) + (Z/M) ... ) + (M/Z) (C) f = (P/A) + (M/Z) (D) f = (P/A) + (M/6Z)
Last Answer : Answer: Option C
Description : is the pre-stressed force applied to tendon of a rectangular pre-stressed beam whose area of cross section is and sectional modulus is . The minimum stress on the beam subjected to a maximum bending moment is (A) f = (P/A) - (Z/M) (B) f = (A/P) - (M/Z) (C) f = (P/A) - (M/Z) (D) f = (P/A) - (M/6Z)
Description : Flexible shafts have ______ rigidity in bending moment. a) High b) Low c) Very high d) Extremely low
Last Answer : b) Low
Description : The strength of a beam depends upon (a) Its section modulus (b) Permissible bending stress (c) Both (a) and (b) (d) None of these
Last Answer : (a) Its section modulus
Description : Which of the following relation is correct regarding free torsional vibrations of a single motor system? a) Independent of modulus of rigidity b) Independent of polar moment of inertia c) Dependent on mass moment of inertia d) Independent of length of shaft
Last Answer : c) Dependent on mass moment of inertia
Description : Increasing which of the following factor would result in increase of free torsional vibration? A. Radius of gyration B. Mass moment of inertia C. Polar moment of inertia D. Length
Last Answer : C. Polar moment of inertia
Description : Increasing which of the following factor would result in increase of free torsional vibration? a) Radius of gyration b) Mass moment of inertiac) Polar moment of inertia d) Length
Last Answer : c) Polar moment of inertia
Description : The radius of gyration of a rectangular section is not proportional to (A) Square root of the moment of inertia (B) Square root of the inverse of the area (C) Square root of the moment of inertia divided by area of the section (D) None of these
Last Answer : (D) None of these
Description : Define: (i) Moment of Inertia (ii) Radius of Gyration
Last Answer : i) Moment of Inertia: Moment of Inertia of a body about any axis is equal to the product of the area of the body and square of the distance of its centroid from that axis. OR Moment of ... at which the entire area is assumed to be concentrated without changing the M. I. about the given axis.
Description : Strength of a shaft a. Is equal to maximum shear stress in the shaft at the time of elastic failure b. Is equal to maximum shear stress in the shaft at the time of rupture c. Is equal to torsional rigidity d. Is ability to resist maximum twisting moment
Last Answer : d. Is ability to resist maximum twisting moment
Description : The load required to produce a unit deflection in the spring is called (a) Modulus of Rigidity (b) Spring stiffness (c) Flexural rigidity (d) Tensional rigidity
Last Answer : b) Spring stiffness
Last Answer : (b) Spring stiffness
Description : The ratio of lateral strain to linear strain is called (a) Modulus of Elasticity (b) Modulus of Rigidity (c) Bulk Modulus (d) Poisson’s Ratio
Last Answer : (d) Poisson’s Ratio
Description : What is the moment of inertia acting on a semicircle of radius 20 mm about the asymmetrical axes? a. 125.663 x 103 mm4 b. 17600 mm4 c. 1500 mm4 d. 8800 mm4
Last Answer : b. 17600 mm4
Description : Find total number coils in a spring having square and ground ends. Deflection in the spring is 6mm when load of 1100N is applied. Modulus of rigidity is 81370N/mm². Wire diameter and pitch circle diameter are 10mm and 50mm respectively. a) 7 b) 6 c) 5 d) 4
Last Answer : a) 7
Description : Determine number of coils in a helical compression spring, if modulus of rigidity is 80 Gpa and spring stiffness is 50 N/ mm. Assume wire diameter and spring index as 8 mm and 5 respectively a. 11.8 turns b. 12.8 turns c. 13.3 turns d. None of the above
Last Answer : b. 12.8 turns
Description : A hollow shaft of 1 m length is designed to transmit a power of 30 kW at 700 rpm. The maximum permissible angle of twist in the shaft is 1o. The inner diameter of the shaft is 0.7 times the outer diameter. The modulus of ... shaft is _______. (a) 43 to 45 (b) 50to 60 (c) 70 to 80 (d) 85 to 100
Last Answer : (a) 43 to 45
Description : In the relation ( T/J = Gθ/L = τ/ R), the letter G denotes modulus of ______ a. elasticity b. plasticity c. rigidity d. resilience
Last Answer : c. rigidity
Description : The relationship between Young’s modulus (E), Modulus of rigidity (C) and Bulk modulus (K) is given by a. E=9CK/(C+3K) b. E=9CK/(2C+3K) c. E=9CK/(3C+K) d. E=9CK/(C-3K)
Last Answer : a. E=9CK/(C+3K)
Description : The ratio of the effective length of a column and minimum radius of gyration of its cross sectionalarea, is known (a) Buckling factor (b) Slenderness ratio (c) Crippling factor (d) None of these
Last Answer : (b) Slenderness ratio
Description : Compression members always tend to buckle in the direction of (a) Vertical axis (b) Horizontal axis (c) Minimum cross-section (d) Least radius of gyration
Last Answer : (d) Least radius of gyration
Description : What is the S.I. unit of sectional modulus? a. mm4 b. mm3 c. mm2 d. m
Last Answer : b. mm3
Description : The maximum twisting moment a shaft can resist, is the product of the permissible shear stress and (A) Moment of inertia (B) Polar moment of inertia (C) Polar modulus (D) Modulus of rigidly
Last Answer : (C) Polar modulus
Description : The graphical representation of variation of axial load on y axis and position of cross section along x axis is called as _____ (a) Bending moment diagram (b) Shear force diagram (c) Stress-strain diagram (d) Trust diagram
Last Answer : (d) Trust diagram
Description : If Z and I are the section modulus and moment of inertia of the section, the shear force F and bending moment M at a section are related by (A) F = My/I (B) F = M/Z (C) F = dM/dx (D) F Mdx
Last Answer : (C) F = dM/dx
Description : Which of the following is incorrect? a. In torsion equation, we use mean torque b. In torsion equation, we use maximum torque c. Many shafts are designed under combined bending and torsion load d. Shafts are also designed for torsional rigidity
Last Answer : a. In torsion equation, we use mean torque
Description : When the shaft is subjected to pure bending moment, the bending stress is given by? a) None of the listed b) 32M/πdᵌ c) 16M/πdᵌ d) 8M/πdᵌ
Last Answer : b) 32M/πdᵌ
Description : Torque and bending moment of 100 kN.m and 200 kN.m acts on a shaft which has external diameter twice of internal diameter. What is the external diameter of the shaft which is subjected to a maximum shear stress of 90 N/mm2? a. 116.5 mm b. 233.025 mm c. 587.1 mm d. 900 mm
Last Answer : c. 587.1 mm
Description : What is the maximum shear stress induced in a solid shaft of 50 mm diameter which is subjected to both bending moment and torque of 300 kN.mm and 200 kN.mm respectively? a. 9.11 N/mm2 b. 14.69 N/mm2 c. 16.22 N/mm2 d. 20.98 N/mm2
Last Answer : b. 14.69 N/mm2
Description : What is the maximum principle stress induced in a solid shaft of 40 mm diameter which is subjected to both bending moment and torque of 300 kN.mm and 150 kN.mm respectively? a. 21.69 N/mm2 b. 28.1 N/mm2 c. 50.57 N/mm2 d. 52.32 N/mm2
Last Answer : c. 50.57 N/mm2
Description : The ratio of maximum bending stress to maximum shear stress on the cross section when a shaft is simultaneously subjected to a torque T and bending moment M, a. T/M b. M/T c. 2T/M d. 2M/T
Last Answer : d. 2M/T
Description : A beam of uniform strength has a. same cross-section throughout the beam b. same bending stress at every section c. same bending moment at every section d. same shear stress at every section
Last Answer : b. same bending stress at every section
Description : In a shaft, the shear stress is not directly proportional to (A) Radius of the shaft (B) Angle of twist (C) Length of the shaft (D) Modulus of rigidity
Last Answer : (C) Length of the shaft
Description : A closely coiled helical spring of radius R, contains n turns and is subjected to an axial loadW. If the radius of the coil wire is r and modulus of rigidity of the coil material is C, the stress developed in the helical spring is (A) WR/ 3 (B) 2WR/ 3 (C) 2WR/ 2 (D) 4WR/ 2
Last Answer : (B) 2WR/ 3
Description : Moment of resistance of a beam should be (a) Greater than the bending moment (b) Less than the bending moment (c) Two times the bending moment (d) None
Last Answer : (a) Greater than the bending moment
Description : In shafts with keyways the allowable stresses are usually ------------ proportional to the twisting moment. a.25% b. 50% c. 75% d. 95%
Last Answer : c. 75%
Description : The ratio of the effective length of a column and minimum radius of gyration of its cross-sectional area, is known (A) Buckling factor (B) Slenderness ratio (C) Crippling factor (D) None of these
Last Answer : (B) Slenderness ratio
Description : A spherical pressure vessel is made of thin magnesium plate 0.25 cm thick. The main diameter of the sphere is 600 cm and allowable stress in tension is 900 kg/cm2. The safe internal gas pressure for the vessel would be a) 0.5 kg/cm2 b) 1.5 kg/cm2 c) 4.5 kg/cm2 d) 5.7 kg/cm2
Last Answer : b) 1.5 kg/cm2
Description : The piston rod of a hydraulic cylinder exerts an operating force of 10kN. The allowable stress in the cylinder is 45N/mm². Calculate the thickness of the cylinder using Lame's equation. Diameter of the cylinder is 40mm and ... is 10MPa. a) 2.05mm b) 4.2mm c) 5.07mm d) None of the listed
Last Answer : c) 5.07mm
Description : According to ASME code, maximum allowable shear stress is taken as X% of yield strength or Y% of ultimate strength. a) X=30 Y=18 b) X=30 Y=30 c) X=18 Y=18 d) X=18 Y=30
Last Answer : a) X=30 Y=18