B B3808 Pages: 2

PART C
Answer any two full questions, each carries 20 marks
7 2) The stresses at a point in a strained material are 50 MPa tensile and 20 MPa (8)

tensile, on two mutually perpendicular planes along with shear stress of 15 MPa.
Find the principal stresses and planes on which they act. Also find the maximum

shear stress and its plane. b) A thick spherical shell of inside diameter 180 mm is subjected to an
internal fluid (8)

pressure of 50 MPa. Find the thickness of the shell, if the maximum permissible
tensile stress in the shell is 190 MPa.

c) State the differences between close coiled and open coiled spring. (4)

8 93) A hollow shaft is to transmit 300 kW power at 80 rpm. If the shear stress is not to (10) exceed
60N/mm? and the diameter ratio is 0.6, find the external and internal diameters assuming the
maximum torque is 1.4 times the mean.

b) Derive an expression for slope and deflection of a simply supported beam with a (10) uniformly

distributed load of intensity ‘w’ per meter throughout the span.

9 9) How can you find slope and deflection in beams using moment area method? (6) 9) Define
effective length of a column. Give the effective lengths for various end (6) conditions.

c) Calculate the safe compressive load on a hollow cast iron column with one end (8)
rigidly fixed and other hinged, of 15 cm external diameter, 10 cm internal diameter

and 10 m in length. Use Euler’s formula with a factor of safety 5 and E = 95
kN/mm?.

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