Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Summer 5th Sem 2151902 Theory Of Machines Previous Question Paper

Enrolment No.___________

**GUJARAT TECHNOLOGICAL UNIVERSITY**

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

**Subject Code: 2151902**

**Date:27/10/2020**

**Subject Name: THEORY OF MACHINES**

**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)**Define: Dynamometer. Classify Dynamometer

**03**

**(b)**Compare single block brake and double block brake.

**04**

**(c)**list experimental methods of mass moment of inertia.

**07**

Explain any one .

**Q.2 (a)**Write briefly gyroscopic effect in an aero plane.

**03**

**(b)**Explain concept of gyroscopic couple.

**04**

**(c)**The mass of the turbine rotor of a ship is 20 tonnes and

**07**

has a radius of gyration of 0.60 m. Its speed is 2000

r.p.m. The ship pitches 60 above and below the horizontal

position. A complete oscillation takes 30 seconds and the

motion is simple harmonic. Solve the following:

(1) Maximum gyroscopic couple

(2) Maximum angular acceleration of the ship during

pitching

(3) The direction in which the bow will tend to turn

when rising, if the rotation of the rotor is

clockwise when looking from left.

**OR**

**(c)**Develop stability of four wheel vehicle moving in curved

**07**

path with neat sketch.

**Q.3 (a)**Define: (1) fluctuation of energy (2) Maximum

**03**

fluctuation of energy (3) co efficient of fluctuation of

energy

**(b)**Enlist dead weight governor. Explain any one.

**04**

**(c)**The

turning moment diagram for a multi cylinder engine

**07**

has been drawn to a scale 1 mm = 500 N-m vertically

and 1 mm = 30 horizontally. The intercepted areas

between the output torque curve and the mean resistance

line, taken in order from one end, are as follows:

+52, -124, +92, -140, +85, -72, and +107 mm2, when the

engine is running at a speed of 600 r.p.m and radius of

gyration is 0.6 m.. If the total fluctuation of speed is not

to exceed ? 1.5 % of the mean. Solve the mass of the

flywheel.

**OR**

**Q.3 (a)**Define: (1) flywheel (2) Maximum fluctuation of speed

**03**

(3) co efficient of fluctuation of speed

**(b)**Enlist spring controlled governor. Explain any one.

**04**

**(c)**Design of flywheel for punching press with help of neat

**07**

sketch.

1

**Q.4 (a)**Define: Clutch. Classify clutch.

**03**

**(b)**Explain Prony brake dynamometer.

**04**

**(c)**An automobile single plate clutch, effective on both side

**07**

consists of a pair of contacting surfaces. The inner and

outer radii of friction plate are 120 mm and 240 mm

respectively. The

co efficient of friction is 0.25 and total axial force is 15

kN. Determine the power transmitting capacity of the

clutch at 500 r.p.m. by using (1) Uniform wear theory

and (2) Uniform pressure theory.

**OR**

**Q.4 (a)**Define: Brake. Classify brake.

**03**

**(b)**Explain belt transmission dynamometer.

**04**

**(c)**Evaluate braking analysis of four wheeler with the help

**07**

of neat sketch.

**Q.5 (a)**Describe free body diagram.

**03**

**(b)**Explain D'Alembert's Principle.

**04**

**(c)**Analyze of dynamics force analysis of slider crank

**07**

mechanism.

**OR**

**Q.5 (a)**Describe shaking force and shaking moment.

**03**

**(b)**Explain Centroid and Center of mass.

**04**

**(c)**Analyze of dynamics force analysis of four bar

**07**

mechanism.

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This post was last modified on 04 March 2021