Janardan Rai Nagar Rajasthan Vidyapeeth 2007 B.Tech Aeronautical Engineering BTAE4-THEORY OF VIBRATION - Question Paper

BIT-V TOTAL PAGES:03
BACHELOR IN TECHNOLOGY
(SEMESTER - V) (AERONAUTICAL)
BTAE4-THEORY OF VIBRATION
TIME: 03 HOURS MAX. MARKS: 75

GENERAL INSTRUCTIONS:
1. Question paper is divided into 3 groups
2. Each group is of 25 marks every
3. Figure to the right in bracket shows mark
4. Assume suitable data if necessary
GROUP A: ans any 3 ques.. ques. No. one is compulsory.
Q.1 Derive expression for work done by a vibrating system (05)
Q.2 Derive expression for series and parallel connected springs in a vibrating system with n number of springs with 1 mass m (10)
Q.3 a) What is critical damping? (10)
b) Derive expression for critical damping and its co efficient of damping for a vibrating system ]
Q.4 Explain vibration isolation and transmissibility with reference to installation of machines to the ground. (10)
Q.5 Briefly discuss the subsequent a) LVDT, b) untuned viscous
damper (10)

GROUP B: ans any 3 ques..
ques. No. six is compulsory.
Q.6 Write short notes on fraham’s reed tachometer (05)
Q.7 A gun barrel of mass 600 kg has a recoil spring of stiffness 294 KN/m if the barrel recoils 1.3m on firing determine the subsequent
a) The initial recoil velocity of the barrel.
b)The critical damping coefficient of the dashpot, which is engaged at the end of the recoil stroke
c)The time needed for the barrel to return to a position five cms from the initial position (10)
Q.8 Derive an expression using differential equations for a 2 degree of freedom system (10)
Q.9 Represent harmonic vibration in complex method (10)
Q.10 Classify various vibrations in detail with graphical
representation
(10)
GROUP C: All ques. are Compulsory.

Q.11 Fill in the blanks (each ques. carries two marks)

(i) Assume a deflection curve of the system that is consistent with the __________.
(ii) __________ developed the rayleigh’s method.
(iii) Dunkerley’s formula has been useful application in case of __________ of freedom system.
(iv) Matrix interaction method interactive for determining __________ & __________.
(v) Holzer’s method is very effective in finding __________ of the system

Q.12 Multiple option ques.. (Each ques. carries two marks)
(i) The maximum displacement of a vibrating body from the mean position is known as __________.
(a) resonance (b) amplitude (c) ultitude (d) peak displacement.
(ii) Equivalent stiffness for springs in series is provided by
(a) (b)
(c) (d)
(iii) For an ‘U’ tube, open to atmosphere at both ends contains a column length ‘I’ of certain liquid, the natural period of oscillation of the liquid column provided by
(a) (b)
(c) (d)
(iv) Critical damping coefficient is denoted by
(a) (b) Cc (c) cc (d) (e) none of these
(v) For steady state vibration phase angle varies from __________.
(a) zero to 900 (b) zero to 1800
(c) zero to 2700 (d) zero to 3600

Q.13 True or false (each ques. carries one mark).
(i) Vibration induced by external force is called free vibration.
(ii) A vibrating system has damping C< Cc critical damping is under damped system.
(iii) Air compressor, IC Engines is examples of forced vibration systems.
(iv) A vibration absorber can undo vibrations completely.
(v) All the vibration measuring instruments can be called as seismic instructions.

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

Earning:   Approval pending.