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Total No. of Questions-l2]

: Four Hours.:- (l) Answer firee questions romfrom Section II.(ll) Answers to the two Sections

lTotal No. of Printed Pages-7t37621-26Maxirnum Marks : 100

Section I and. hree questionsshould be written in separate

and give their practical[8]mechanisms [4]

S.E. (Mechanical) (II Sern.) EXAMINATION, 2010THEORY OF MACHINES AND MECHANISMS-I(2003couRsE)

firne.^r'.B.answer-books.(ili) Neat diagrams must be drawn wherever necessary.(lu) Figures to the right indicate full marks.(u) Assume suitable data, if necessary.

t4l. (c)

(b)\c)

SECTION IUnit I

Define the following terms :(l) Structure(li) Mechanism(ill) Kinematic pair(iu) Constrained motion.Explain inversions of four bar chainapplications.Determine degree of freedom for the following

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Unit II3. (a) Explain "Davissteeringgearmechanisrr'' nd"Achermann teering

gear mecnauism" rn detall. t81(b) Explain contstn-rctionof Hooke's Joint and derive equation for

angular velocity ratio for single Hooke's joint.,:, Differentiate between single and double Hooke?s.oint. 121

Or4. (a) Explain with neat sketch :

(, Genevamechanism.(ii) Hart's straight line mechanism.

@) State and prove the condition of correct steering for a four-

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Unit III(o) Explain Freudenstein's theorem in instantaneous centre. [4](O) -t'lg.3 showsa crank OA 110mm long rotating clockwiseabout

'O' at 160 r.p.m.,AB is connecting od 440 mm iong. A point'C' on AB is 165 mm frorn ,A, the rocl CE 3gb mm long isattached. The rod CE slides in a slot ir a trunnion at D.The end E is connectedby a Iink EF dgO mm long to thenonzonra[y moung sltdes !' tor the mechanismshown in thefigure. Determine the velocity of slider ,F using instantaneouscentre method. tl4l

o.

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ll . \it)(6) '

of the slider Dvelocities of links BC CDat O2B when the and

(force atequired D i s

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7. (a)(b)

(a)

Unit IV .Explain .Coriolis componentof acceleration. tSlrrg. D shows a qurck retum motion mechanism n which thedriving crank OA rotates at 120 r.p.m. in a clockwisedirection.For the position shown, determine the magnitude and directiono f :(l) Acceleration of b.lockD(,l) Angular accelerationof slotted bar eB. t131

8.

rlg. ?' O r

Dxpraln tlletn's constructronacceleraticn of piston of an

ror oef,ell natron of velocity andt6l

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(b) In a slider mechanism he crank is 200 mm long and connectingrod 750 mm long. Find the velocity and accelerationofpiston ancl connectingrod by.velocity polygon method whenthe siider has moved through 350 mm from top deadcentre position. Assume crank rotates at uniform speed of720 t.p.m. t10l

Unit V

Explain Trifiller Suspensionmethod. t6l, (a)(b) The connecting rod of an engine has a length equal to

200 mm between centres and has a mass equal to 2.5 kg.Its centre of gravity is at 80 mm from the big end (crankpin) and ihe radius of gyration about an axis passing hroughthe centre of gravity perpendicular to the plane of motionis 100 mm. Find :(i) Thetwo massdlnamically equivalentsysternwhen onemass

is placed at the small end(il) Correction couple if masses are placed at the two ends

and the angular acceleration of the connecting rod is100 rad./sec2 lockwise. t101

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10. (o)Or

With the.help ofneat schematicdiagram derive {iequencyequationof compoundpendulum. tSl

(6) What do you mean by "correctioncouple" ? When do we needf o n o n c i d a r i i ?Write a ' short note on D' Alemberts principle.

Urit VIExplain the following terms :(i) Type sl.nthesis(ii) Number synthesis(iii) DimensionalsynthesisDesigrr a four bar mechanism to co-ordinate threetions of the input and output links as follows :

0r = 20', 02 = 35', 0B = 50"0r = 35., z = +s",da = 60":

OrExplain Coupler curve sJmthesis.Explain overlay method for locating precision positionhor racnanl i -at -

Deterrrrine the link lengths of the slider crank linkagea stroke of 600 mm and time raLio 1 : 20-

t611. (a)

(c,

(6)

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t6lin four

t61to have

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L2- (a)(6)

(c)

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