Yashwantrao Chavan Maharashtra Open University 2006 Certification TML Strength of Materials - exam paper

TML051/EE/20070811
Strength of Materials
Time : 180 minutes Marks : 100
Instructions for the students :
1. All ques. are compulsory.
2. “Long ans kind ques. (LAQ)” is a supply kind ques. of 20 marks,
which require typical ans of about 60-80 lines in about 32-40 minutes.
3. “Short ans kind ques. (SAQ)” is a supply kind ques. of five marks,
which require typical ans of about 15-20 lines in about 08-10 minutes.
4. Use of non-programmable kind of scientific calculator is allowed.
5. Draw neat diagrams wherever necessary.
6. presume suitable data if necessary.

Long ans kind ques. (LAQ’s)

1. (a) discuss the terms :
i) Elasticity ii) Plasticity iii) Creep
(b) A short post constructed from a hollow circular tube of
aluminum supports a compressive load of 54 kN. The inner
and outer diameter of the tube are 3.6
1
d = cm and 5
2
d = cm
and respectively and its length is = 40 cm. The shortening of
the post due to the load is measured as 0.022 cm. Determine
compressive stress and strain in the post. (Assume that post
does not buckle under the load.)


2. (a) discuss the terms :
i) Stress Concentration ii) Fatigue
(b) The mechanical assembly shown in the figure 1. consists of a
copper tube, a rigid and plate and 2 steel cable with
turnbuckles. The slack is removed from the cables by rotating
the turnbuckles until the assembly is sung, but no initial
stresses. (Further tightening of the turnbuckles will produce a
prestressed condition in which the cables are in tension and
tube in compression.
Determine :
a) Forces in tube and cables when turnbuckles are tightened
by ‘N’ turns.
b) Shortening of tube.

3. (a) A solid shaft in a rolling mill transmits 20 kW at two Hz.
Determine the diameter of shaft if the shearing stress is not to
exceed 40 mPa and the angle of twist is limited to 60 in a
length of three m.
Use G = 83 GPa.
(b) Derive the torsional formula.
10
10
4. Draw shear force and bending moment diagram for the provided
figure 2.

Short ans kind ques. (SAQ’s)
5. describe :
i) Hookes legal regulations
ii) Poisson Ratio

6. discuss the terms ‘Misfits’. 5
7. State the assumptions of Torsion formula. 5
8. describe :
i) Shear force
ii) Bending Moment

Earning:   Approval pending.