Strength of Material (Part-3) (General Engineering) (SSC JE)

Total Questions: 50

31. What is the moment of inertia of a quarter circle with respect to x-axis which is passing through the center of a circle whose radius is 20 mm.? [MPSC AE PRE.- 23.06.2019 ]

Correct Answer: (a) 3.14 cm⁴
Solution:

32. The steel bar ABCD of varying sections is subjected to the axial forces as shown in the figure below. Find the value of P necessary for equilibrium. If E = 210 kN/mm² , determine the total elongation of the bar [JPSC AE (GEN. ENGG)-2013 ]

Correct Answer: (b) P = 84 kN; 1.11 mm
Solution:


33. The centre of gravity circular cone of height 'h' lies at a distance ______ from vertex along the axis of rotation. [MPSC AE PRE.-08.07.2018 ]

Correct Answer: (b) 3h/4
Solution:


34. ________ tests are used to indicate toughness of a material under shock loading conditions. [IREL Diploma Trainee-11.09.2022 ]

Correct Answer: (c) Impact
Solution:

35. What will be the coordinates of the centroid (C) of the semi-circular lamina (OAB) shown in the figure? [‘O’ is the origin ‘R’ is the Radius of semi-circular lamina] [NHPC JE (EE) 05.04.2022 (Shift-I) ]

Correct Answer: (a)
Solution:



36. Work is measured in________. [IREL Diploma Trainee-11.09.2022 ]

Correct Answer: (c) Joules
Solution:

Work–The physical quantity which cause displacement in the direction of force.
W = Force × displacement
W = F.S. cos θ
Unit– N-S = Joules
Ohm = Electric resistance
Mho = Electrical conductance
Ampere = Electric current.

37. Strength of a material is defined as [BPSC AE (Civil) 25.03.2022 ]

Correct Answer: (c) resistance to deformation
Solution:

The strength of the material is its ability to withstand an applied stress without failure.

• When an external force acts on a body the body tends to undergo some deformation due to cohesion between the molecules the body resists deformation. This resistance by which material of the body opposes the deformation is known as strength of material.

• Within a certain limit (i.e. in the elastic stage) the resistance offered by the material is proportional to the deformation brought out on the material by the external force. Also within this limit the resistance is equal to the external force (or applied load). But beyond the elastic stage the resistance offered by the material is less than the applied load in such case the deformation continues until failure takes place.

• Within elastic stage the resisting force equals applied load. This resisting force per unit area is called stress or intensity of stress.

38. A circular solid disc of uniform thickness 20 mm, radius 200 mm and mass 20 kg, is used as a flywheel. If it rotates at 600 r.p.m., the kinetic energy of the flywheel, in joules is [BPSC AE (GEN. ENGG.)-29.03.2019 ]

Correct Answer: (b) 790
Solution:

39. An annular disc has a mass m, inner radius R and outer radius 2R. The disc rolls on a flat surface without slipping. If the velocity of the centre of mass is v, the kinetic energy of the disc is [BPSC AE (GEN. ENGG.)-29.03.2019 ]

Correct Answer: (b) 11/16 mv²
Solution:



40. A circular object of radius r rolls without slipping on a horizontal level floor with the point of contact between the object and the floor is [BPSC AE (GEN. ENGG.)-29.03.2019 ]

Correct Answer: (a) zero
Solution: