**Roll No. ......................**

**Total No. of Questions : 09]**

**B. Tech. (Sem. – 3rd)**

**THEORY OF MACHINES-I**

**SUBJECT CODE : ME-203**

**Paper ID : [A0802]**

**Time : 03 Hours**

**Instruction to Candidates:**

1. SECTION-A
is COMPULSORY consisting of TEN questions carrying

TWO marks each.

2. SECTION-B
contains FIVE questions carrying FIVE marks each and

students has to
attempt any FOUR questions.

3. SECTION-C contains THREE questions
carrying TEN marks each and

students has to
attempt any TWO questions.

**SECTION-A**

l.
Write short notes on :

(a) What is High Pair ?

(b) Explain why higher cannot be inverted?

(c) Explain Acceleration Centre of a Link.

(d) For the design of bearing why we use
uniform pressure theory ?

(e) Write the applications of single plate
clutch.

(f) Write the applications of cone clutch.

(g) What is the Law of Belting ?

(h) What is the advantage of using double
Hooke’s joint ?

(i) What is the difference between governor
and flywheel ?

(j) Why cycloidal profile is preferred over
S.H.M. profile for cams used

in high speed applications ?

2.
In Fig-1 a slider crank chain is shown

Which
mechanism is obtained from the chain if link 3 is fixed ? Explain.

3.
For the configuration shown in Fig.-2, determine V

_{D}by instantaneous
centre
method if V

_{A}= 635 mm/sec with turning counter clockwise.
4.
The initial tension in a flat belt drive is 1800 N. The angle of lap on the

smaller
pulley is 170°. The coefficient of friction of the belt and pulley surface is
0·25. The pulley has a diameter of 0·9 m and it runs at 540 r.p.m. Determine
the power that can be transmitted at the above speed. Neglect centrifugal
tension.

5. In a turning moment diagram, the areas above and below the mean

torque line taken in order are 395, 785, 140, 440, 1060 and 370 mm
2, having scales of 1 mm = 5 N-m and 1 mm = 10° along Y and X axis
respectively. Find mass of flywheel at a radius of gyration 150 mm and maximum
fluctuation of speed is limited to 1·5% of mean speed which is 1800 r.p.m.

6. A band brake is lined with 10 wooden blocks each of which
subtends an

angle of
18° at the centre of the brake drum. Find the ratio between the greatest and
the least tensions in the band when the brake is in action. Take = 0·36.

**SECTION-C**

7. Two parallel shafts indicated in Fig.-3 are connected by an
intermediate

shaft with
a Hooke’s joint at each end. Show that the joints should be oriented to obtain
a constant angular velocity ratio between the driving and driven shafts.

The intermediate shaft of the above arrangement has a mass moment of
inertia 3 × 10–3 kg-m 2 and is inclined
at 30° to the axes of the driving and driven shafts. If the driving shaft
rotates uniformly at 2400 r.p.m. with a steady input torque of 300 N-m, determine
the maximum fluctuation of output torque

paper.com

8. A governor is shown in Fig.-4 schematically. The two links which
carry

the balls of mass m each are connected by a spring of stiffness k
and has a natural length of 2e. Find out the expression for the inclination of
the links with vertical when the governor rotates at a speed .

9. For a cam follower system shown in Fig.-5, draw the displacement

diagram for
the follower and cam profile. Motion of the follower is as follows : Rise
through 20° in 90° cam rotation in SHM, dwell in 90° cam rotation, S.H.M. fall
in 90° cam rotation, dwell during 90° cam rotation. If N = 2500 r.p.m., find
the max. angular velocity and angular acceleration of the pivoted follower

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