Strength of Material

June-2006
SOM

Q.1 (a) Draw the engineering curve for mild steel on stress Vs strain graph and answer
the following: 4
(1) Ultimate stress is higher than breaking stress on the curve. 3
(2) Elastic limit is higher than proportional limit. 3

(b) A vertical bar of uniform section fixed at both its ends is axially loaded at
intermediate sections by 5000N and 3000N as shown in fig. Find the reactions at
both ends. 10

Q.2 Draw shear force and bending moment diagrams for simply supported beam at
ends shown in fig. 2. 20

Q.3 (a) Write assumptions made in the theory of pure bending. 8

(b) Three beams have the same length, same allowable bending stress and are
Subjected to same maximum bending moment. The cross-sections of the beams
are a circle , a square and a rectangle with depth twice the width . Find the ratio of
the circular and rectangular beams with respect to the square beam. 12

Q.4 (a) A cantilever of length 6 meters carries a point load of 100 N at the free end.
Determine the slope and deflection at the free end.
(Take 1xx =8.4x107mm4 and E = 200kN/mm2) 14

(b) What do you understand by roller, hinged & fixed end supports. 6

Q.5 (a) Differentiates between buckling load and crushing load. 6

(b)A hollow alloy tube of 4 meters long with external and internal diameter equal to
40 mm and 25 mm respectively was found to extend by 5mm under a tensile load
of 50 kN. Find the buckling load for the tube, when used as a column with both
ends pinned. Also find the safe compressive load for the tube, with factor of safety
of 2. 14

Q.6 (a) Explain torsional rigidity of shaft. 5

(b) A shaft has to transmit 120 KW at 160 rpm. If the shear stress is not to exceed 70 N/mm2 and twist in a length of 3.5 m must not exceed 1°, find a suitable diameter. Take C= 8x104 N/mm2. 15

Q.7 (a) Define spring constant for open helical spring. 5
(b) Find the expression for the stiffness of spring (open helical spring). 15

Q.8 Write short notes on any four of the following: (5x4)
(a) The values of poison’s ratio.
(b) Bulk modulus
(c) Circumferential stresses in seamless thin walled cylinder
(d) Long column
(e) Eccentric loading on vertical column.

Plz. stay connected for updates.

Material Science

May 2007
Material science

Q.1 (a) Discuss different type of crystal imperfections. (10)
(b) Explain various mechanical properties of a material (10)

Q.2 (a) What is corrosion? Explain how it can be prevented? (10)
(b) What is cold working? How properties like hardness, strength change typically
for a metal when it is cold worked? (10)

Q.3 (a) What are various type of cast iron? Give the composition and use of three of
them. (10)
(b) Describe the Bessemer process for the manufacture of steel. (10)

Q.4 (a) Give the affect of the following alloying elements on properties of steel: (10)
(1) Chromium
(2) Vanadium
(3) Silicon
(4) Tungsten
(5) Molybdenum
(b) Discuss the composition, properties and uses of spring steel and silicon steel. (10)

Q.5 (a) Discuss the composition, properties and uses of following alloys of aluminium:
(1) Duralumin
(2) Magnelium
(b) Discuss the characteristics of bearing materials. Give the composition and use of
any one bearing material. (10)

Q.6 (a) Differentiate between thermosetting and thermoplastics. Give the properties and
use of these plastics. (10)
(b) Name the application where fibers are more suitable than plastics. Compare
inorganic and organic fibers. (10)

Q.7 (a) Discuss various heat insulating materials and their uses. (10)
(b) Give the properties and engineering applications of china clay and rubber. (10)

Q.8 Write short notes on any four of the following: (5x4)
(a) PUF
(b) HSS

(c) Smart Materials
(d) Super Conductivity
(e) Zinc& its alloys

(f) Plastic coating


June 2006
Material Science

Q.1 Select suitable material for each of the following application:
(a) Lathe bed
(b) Gear Wheel for a piece of office equipment where there is a possibility
of lubricant staining the stationery.
(c) Motor Car body panel.
Give reasons for selection of particular materials.
OR
Briefly explain the difference between a crystalline solid and an amorphous solid and give an example of each type.

Q.2 (a) What is atomic radius? Give its value for an FCC structure.
(b)Draw (112) and (111) planes in a simple cubic cell.

Q.3 (a) What is the difference between “pure metal” and “alloy”?
(b) Give the effects of Chromium, Nickel and Silicon when added in
steel as alloying material, on the mechanical properties of steel.
Q.4 (a) What is “dry corrosion” and “wet corrosion”?
(b) State the essential difference between the cold-working and hot-
working on metals.

Q.5 Describe any process for the manufacture of steel or pig iron.

Q.6 (a) State the main difference between thermoplastic and thermosetting
polymeric materials.
(b) Give the composition and uses of HSS and silicon steel.
(c) Give four alloys of copper.

Q.7 (a) Name some bearing materials and their applications.
(b) State the essential difference between cast iron and plain carbon
steel.
(c) Give four important properties of plastics.

Q.8 Write brief technical notes on any Two of the following:
(a) Thermocole, cork and china clay.
(b) Uses of polyethylene in industries.
(c) Various types of cast irons and their uses.
Plz. Stay connected for more updates.