Recent questions tagged strength-of-materials

Description : State and explain perpendicular axis theorem of moment of Inertia.

Last Answer : Perpendicular axis theorem: It states MI of a plane lamina about an axis perpendicular to the plane of lamina and passing through the centroid of the lamina is equal to the addition of the moments of ... OY are mutually perpendicular and OZ is the axis perpendicular to plane XY of the lamina.

Description : Explain the theory of pure torsion.

Last Answer : A shaft is a rotating part of machine which transmits power from one point to other. When a force acts tangentially at a point on the surface of the shaft it rotates or twist. The twisting is due to ... in the material of the shaft is subjected to pure shear.  Torsional Equation is   

Description : Define the core of a section.

Last Answer : The centrally located portion of a within which the load must act so as to produce only compressive stress is called a core of the section.

Description : State the condition for no tension at the base of a column.

Last Answer : If the load acting in the middle third area or core of the section, then the material experiences only compressive stress without producing tensile stress. i.e. Direct stress is equal to bending stress. Minimum stress is zero, such condition is said to be no tension condition.  

Description : Define section modulus and neutral axis.

Last Answer : Section Modulus: It is the ratio of M. I. of the section about the neutral axis and the distance of the most extreme fiber from the neutral axis. Neutral Axis: It is the axis shown in cross ... The intersection of the neutral layer with any normal cross section of a beam is called as neutral axis.

Description : Define point of contra-flexure of a loaded beam with sketch.

Last Answer : Point of Contra-flexure: It is the point in bending moment diagram where bending moment changes its sign from positive to negative and vice versa. At that point bending moment is equal to zero. This point is called as point of contra-flexure.

Description : Draw stress-strain diagram for mild-steel rod and show different limits on it. 

Last Answer : Where, A = Limit of proportionality B = Elastic limit C = Upper yield point D = Lower yield point E = Ultimate load point F = Breaking point

Description : State the relation between Young’s modulus and bulk modulus. 

Last Answer : E = 3K(1 - 2 µ ) Where, E= Young’s Modulus  K= Bulk Modulus  µ= Poisson’s Ratio

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.