Summer 2016 Strength of Materials Question Paper

************

GUJARAT TECHNOLOGICAL UNIVERSITY
DIPLOMA ENGINEERING – SEMESTER – III • EXAMINATION – SUMMER 16
Subject Code: 3331904 Date: 24.05.2016
Subject Name: Strength of Materials
Time: 02:30 PM TO 05:00 PM Total Marks: 70

Instructions:
1. Attempt all questions.
2. Make Suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
4. Use of programmable & Communication aids are strictly prohibited.
5. Use of only simple calculator is permitted in Mathematics.
6. English version is authentic.

************

Q.1 Answer any seven out of ten. 14

1. Explain Hooke’s Law.

2. Explain Composite Section.

3. Define resilience & proof resilience.

4. Explain perpendicular axis theorem with neat sketch.

5. Define S.F. & B.M.

6. Define Neutral axis.

7. Define slope & deflection.

8. Define long column & short column

9. Define Polar moment of inertia & angle of twist.

10. Differentiate rivet joint & welded joint

Q.2 (a) Define Stress, Strain and modulus of elasticity. 03

OR

(a) An axial tension of 50kN is applied to a rod of 4m length and 500mm2 in sectional area.
The increase in length is found to be 2mm. calculate stress and strain. 03

(b) Differentiate statically determinate and indeterminate beam. 03

OR

(b) Draw B.M. diagram for a beam shown in figure-1. 03

(c) Find Ixx of the section shown in figure-2. 04

OR

(c) Explain parallel axis theorem. 04

(d) A 10mm long mild steel rail section is fixed at 3000 C temperature. If temperature increases
 by 600 C find stress in rail section for 5mm gap at one end. 04

OR

(d) An axial compressive load of 80kN is suddenly applied to a steel rod of 16mm diameter and 1m length. Find strain energy developed in the bar. Take E= 2 x 105 N/mm2 04

Q.3 (a) Draw S.F. diagram for a beam shown in figure-3. 03

OR

(a) Draw B.M. diagram for a beam shown in figure-3. 03

(b) Assumptions made in theory of bending. 03

OR

(b) Calculate bending stress for a simply supported beam 6m in span. The width of beam is
300mm and depth is 600mm. The beam carries a u.d.l of 40kN/m over the whole span. 03

(c) Draw the shear stress distribution diagrams of rectangular, hollow rectangular, circular
and hollow circular sections. 04

OR

(c) A beam having cross section dimension 300x450mm is subjected to shear force of 100kN.
Find the maximum shear stress and draw the shear stress distribution diagram. 04

(d) A simply supported beam 3m in span is subjected to u.d.l. of 10kN/m over entire span with central point load of 5kN. The cross section of beam is 150x300mm. calculate the maximum
slope for the beam. 04

OR

(d) A simply supported beam 3m in span is subjected to u.d.l. of 10kN/m over entire span with central point load of 5kN. The cross section of beam is 150x300mm. calculate the maximum deflection for the beam. 04

Q.4 (a) State equation of torsion and give assumption for theory of torsion. 03

OR

(a) Find the torque which a shaft of 200mm diameter can transmit safely if, the permissible shear stress is 50N/mm2. 03

(b) Limit of eccentricity. 04

OR

(b) A 300mm square column is subjected compressive force of 150kN at an eccentricity of 125mm along any axis. Find maximum & minimum stresses and draw stress diagram. 04

(c) Find normal, tangential and resultant stress on plan “EF” shown in figure-4. 07

Q.5 (a) Draw the core of section diagrams of rectangular section, circular section, Tsections
and I-section. 04

(b) Explain column end conditions and effective length. 04

(c) Explain principal plane and principal stress. 03

(d) Classification of engineering materials based on physical properties. 03

************

10kN 10kN/m
0.5m 0.5m 1m
Fig-1
3kN 2kN/m
2m 2m 3m
Fig-3
3kN
100m
m
50mm
15m
m
50mm
15mm
15m
m
Fig-2
Ø=450
2
1   200N /mm
2  100N /mm
2
2  100N /mm
Fig-4
F
E