Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 3rd Sem 3130608 Mechanics Of Solids Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

**BE - SEMESTER? III EXAMINATION ? SUMMER 2020**

**Subject Code: 3130608**

**Date:04/11/2020**

**Subject Name: Mechanics of Solids**

**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.**

**Marks**

**Q.1**

**(a)**State's Law of Parallelogram of forces.

**03**

**(b)**Define force and writes its characteristics.

**04**

Find the magnitude and direction of resultant of

**(c)**force system shown in fig. 01.

**07**

What is meant by free body diagram? Draw free

**Q.2**

**(a)**body diagram for box place on a table.

**03**

Define : (1) Isotropic material (2) Anisotropic

**(b)**material (3) Homogeneous material (4)

**04**

Orthotropic material.

Find the minimum (least) value of force P to

keep the sphere in the position shown in fig. 02.

**(c)**The radius of sphere 1 is 5cm and sphere 2 is

**07**

10cm. The weight of sphere 1 is 100N and sphere

2 is 200N.

**OR**

Draw shear force diagram and bending moment

**(c)**diagram for a beam shown in fig. 03.

**07**

What is difference between deficient truss and

**Q.3**

**(a)**redundant truss.

**03**

**(b)**Explain types of supports with usual notations.

**04**

**(c)**Find the CG of plane lamina shown in fig 4.

**07**

**OR**

Explain : (1) Poisson's ratio (2) Hook's law (3)

**Q.3**

**(a)**Bulk modulus.

**03**

A bar of 3m long and 20mm diameter is rigidly

fixed in two

supports at certain temperature. If

temperature is raised by 60? C, find the thermal

**(b)**stress and strain of the bar. Also find thermal

**04**

stress and strain if support yields by 2 mm. Take

= 12 x 10-6 / ?C and E = 2x105 N/mm2.

State and explain with figure Pappu's ?Guildinus

**(c)**theorem of surface area of Revolution.

**07**

**Q.4**

**(a)**Enlist the assumptions made in theory of torsion.

**03**

A beam simple supported and carries an U.D.L.

of 50 kN/m over whole span. The size of beam

**(b)**is 150mm x 400mm.. If maximum stress in the

**04**

material of beam is 100N/mm2 find the span of

beam.

Determine the centroid of the section shown in

**(c)**fig. 05.

**07**

1

**OR**

A load of 10 kN is to be raised with help of a

**Q.4**

**(a)**steel wire. Find the minimum diameter of the

**03**

wire, if the stress is not to be exceed 80 N/mm2.

**(b)**Explain types of beams with notations.

**04**

Determine moments of inertia of a section shown

**(c)**in fig. 06 about horizontal centroidal axis.

**07**

Define: (1) Shear Force (2) Bending Moment (3)

**Q.5**

**(a)**Points of contraflexure

**03**

Derive the relation between : (1) Young's

**(b)**Modulus (2) Modulus of Rigidity (3) Possion's

**04**

Ratio

A hollow steel shaft, 3m of length must transmit

a torque of 25 kNm. The total angle of twist in

this length is not to exceed 2.5? and the allowable

**(c)**shearing stress in the material is 90 MPa.

**07**

Calculate the inside diameter of the shaft and

thickness of the metal. G = 85 GN/m2.

**OR**

Draw shear stress distribution diagram for : (1) I

**Q.5**

**(a)**section (2) Circular section (3) Triangular

**03**

section

Explain assumptions made in theory of pure

**(b)**bending.

**04**

A square prism of metal 60mm x 60mm in cross

section and 300mm long is subjected to a tensile

stress of 450 MPa along its longitudinal axis,

lateral compression of 240 MPa and lateral

**(c)**tension of 120 MPa along the pair of sides.

**07**

If E = 150 GPa, calculate the changes in

dimensions, change in volume of metal.

? = 0.36.

2

3

This post was last modified on 04 March 2021