JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech II STRENGTH OF MATERIALS – I Previous Question Paper (May/June - 2019 - R13)

Define stress and strain.

Define three moduli of elasticity and state the relation between them.

List the assumptions made in simple bending.

Describe Mohr’s circle.

Draw the S.F and B.M diagram for a simply supported beam carrying a uniformly varying load from zero at each end to w per unit length at the center.

What is a point of contra-flexure? Is the point of inflexion and contra flexure same.

State the limitations of maximum shear stress theory.

Explain Maximum principal strain theory.

Determine the maximum slope and deflection of a cantilever beam if a point load of 10kN acts at a distance of 3m from free end, the span of the beam is 4.5m EI = 210 MNm2.

What is the advantage of conjugate beam method over other methods used for determining the deflection?

A bar of 30 mm diameter is subjected to a pull of 60 kN. The measured extension on gauge length of 200 mm is 0.09 mm and the change in diameter is 0.0039 mm. Calculate the Poisson’s ratio and the values of the three moduli.

The modulus of elasticity and rigidity of a given material are 200 GPa and 80 GPa respectively. Find the Poisson’s ratio.

The extension in a rectangular steel bar of length 400mm and thickness 3mm is found be 0.21mm. The bar tapers uniformly in width from 20mm to 60mm E for the bar is 2×105 N/mm2. Determine the axial load on the bar.

Two vertical rods one of steel and the other of copper are each rigidly fixed at the top and 50cm apart. Diameters and lengths of each rod are 2cm and 4m respectively. A cross bar fixed to the rods, at the lower ends carries a load of 5000 N such that the cross bar remains horizontal even after loading. Find the stress in each rod and the position of the load on the bar. Take E for steel = 2 × 105 N/mm2 and E for copper = 1×105 N/mm2.

What is meant by negative or hogging BM.

A Simply supported beam of effective span 6 m carries three point loads of 30 KN, 25 KN and 40 KN at 1m, 3m and 4.5m respectively from the left support. Draw the SFD and BMD is indicating values at salient points.

Draw the shear force and bending moment diagrams for a simply supported beam of span 5m. Beam carries a uniformly varying load of 800N/m at left hand end and 1600 N/m at the right hand end. Calculate the position and magnitude of maximum bending moment.

A simply supported beam of 6 m span is subjected to a uniformly distributed load of 20 kN/m throughout the span. Find the S.F and B.M.

A wooden beam 200 mm × 300 mm is simply supported over a span of 5 m. When a concentrated load ‘W’ is placed at a distance ‘a’ from the left support, the maximum bending stress in beam is 15 MPa and maximum shear stress is 1.0 MPa. Determine ‘W’ and ‘a’.

A beam of size 200 mm wide, 250 mm deep carries a uniformly distributed load of w kN/m over entire span of 5 m. A concentrated load 1 kN is acting at a distance of 1.5 m from the left support. If the bending stress at a section 2 m from the left support is not to exceed 3.0 N/mm2. Find the load w.

Sketch the shear stress distribution for symmetrical I section.

A cantilever beam of T-section of 200×250×12 mm with 200mm side horizontal has a length of 2.5 m and is subjected to a point load of 3 kN at free end. Calculate the shearing stress and plot the stress distribution across the cross-section of the beam.

The deflection of the girder at the points under the two loads

Find the maximum deflection using Maculay’s method. Take E = 210 × 106 kN/m2, I = 64 × 10-4 m4.