Previous year question paper for SOM (Diploma Mechanical Engineering 3rd)

1. Stresses and Strains (08 hrs)

1.1. Concept of load, stresses and strain

1.2. Tensile compressive and shear stresses and strains

1.3. Concept of Elasticity, Elastic limit and limit of proportionality.

1.3.1. Hook’s Law

1.3.2. Young Modulus of elasticity

1.3.3. Nominal stress

1.3.4. Stress strain diagram

1.3.5. Yield point, plastic stage

1.3.6. Ultimate strength and breaking stress

1.3.7. Percentage elongation

1.3.8. Proof stress and working stress

1.3.9. Factor of safety

1.3.10. Poisson’s ratio

1.3.11. Shear modulus

1.4. Longitudinal and circumferential stresses in seamless thin walled

cylindrical shells (derivation of these formulae not required)

2. Resilience (06 hrs)

2.1 Resilience, proof resilience and modulus of resilience

2.2 Strain energy due to direct stresses

2.3 Stresses due to gradual, sudden and falling load.

2.4 Numerical problems

3 Moment of Inertia (06 hrs)

3.1. Concept of moment of Inertia and second moment of area

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3.2. Radius of gyration , section modulus

3.3. Theorem of perpendicular axis and parallel axis ( without derivation)

3.4. Second moment of area of common geometrical sections: Rectangle,

Triangle, Circle (without derivation) Second moment of area for I,T,

L, Z section

3.5 Simple numerical problems.

4. Bending Moment and Shearing Force (10 hrs)

4.1 Concept of beam and type of loading

4.2 Concept of end supports-Roller, hinged and fixed

4.3 Concept of bending moment and shearing force

4.4 B.M. and S.F. Diagram for cantilever and simply supported beams with

and without overhang subjected to concentrated and U.D.L.

4.5 Simple numerical problems

5. Bending stresses (08 hrs)

5.1 Concept of Bending stresses

5.2. Theory of simple bending

5.3. Use of the equation f/y = M/I = E/R

5.4. Concept of moment of resistance

5.5. Bending stress diagram

5.6. Calculation of maximum bending stress in beams of rectangular, circular,

and T section.

5.7 Permissible bending stress Section modulus for rectangular, circular

and symmetrical I section.

5.8 Simple numerical problems

6 Columns (08 hrs)

6.1. Concept of column, modes of failure

6.2. Types of columns

6.3. Buckling load, crushing load

6.4. Slenderness ratio

6.5. Factors effecting strength of a column

6.6 End restraints

6.7 Effective length

6.8 Strength of column by Euler Formula without derivation

6.9. Rankine Gourdan formula ( without derivation)

6.10 Simple numerical problems

7 Torsion (08hrs)

7.1 Concept of torsion- difference between torque and torsion.

7.2 Use of torque equation for circular shaft

7.3 Comparison between solid and hollow shaft with regard to their strength

and weight.

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7.4 Power transmitted by shaft

7.5 Concept of mean and maximum torque

7.6 Simple numerical problems

8. Springs (10 hrs)

8.1. Closed coil helical springs subjected to axial load and impact load

8.2 Stress deformation

8.3 Stiffness and angle of twist and strain energy

8.4 Proof resilience

8.5 Laminated spring (semi elliptical type only)

8.6 Determination of number of plates

8.7 Simple numerical problems