Quiz 1 Unit 2 TOM I 1 The

Quiz 1 Unit - 2 TOM I

1) The periodic time (tp) is given by a) 2π / ω b) ω / 2π c) 2π x ω d) π / ω 2) The velocity of particle moving with simple harmonic motion is _______ at the mean postion. a) zero b) minimum c) maximum d) none of above

3) The velovity of a particle (v) moving with simple harmonic motion, at any instant is given by ______________ 4) The maximum acceleration of a particle moving with simple harmonic motion is _______ a) ω b) ω. r c) ω2. r d) ω2 / r

5) The frequency of oscillation for simple pendulum is _____ 6) When the rigid body is suspended vertically and it oscillates with a small amplitude under the action of force of gravity, the body is known as, a) simple pendulum b) Torsional pendulum c) Compound pendulum d) Second’s pendulum

7) The frequency of oscillation of a compound pendulum is, 8) The equivalent length of a simple pendulum which gives the same frequency as the compound pendulum is a) h / (k 2 + h 2) c) h 2 / (k. G + 2 h 2) b) (k. G 2 + h 2) / h d) (k. G 2 + h 2) / h 2

9) The center of percussion is below the center of gravity of the body and is at a distance equal to a) h / k. G b) h. k. G c) h 2 / k. G d) k. G 2 / h 10) The inertia force are produced because of the _______ accelerating components of a machine. a) shape b) size c) mass d) all of above

11) _____ force is an imaginary force, which when acts on a rigid body, bring it in an equilibrium position. a) centrifugal b) inertia c) pressure d) centripetal 12) Unit of mass moment of inertia is ____ a) m 4 b) N / m 2 c) kg - m 2 d) kg / m 2

13) Fig. shows T – θ disgram for _______ a) single cylinder double acting steam engine b) four stroke engine c) multicylinder engine d) all of above

14) Fig. shows T – θ diagram for _______ a) single cylinder double acting steam engine. b) four stroke engine c) multicylinder engine d) all of above

Quiz 2 Unit - 2 TOM I

1) MMI of a rigid body measures the _____ a) resistance to angular acceleration c) resistance to angular velocity b) resistance to angular deformation d) all of above 2) “The resultant force acting on a body together with the inertia force, are in equilibrium”. This is _____ principle. a) Newtons c) Archimedes b) D’Alemberts d) none of above

3) For simple pendulum ( α / θ ) = _______ a) L / g b) g / L c) g. L d) none of above 4) For trifilar suspension ( α / θ ) = _______ a) (g. x. y) / (l. k. G 2) b) (g. h) / (k. G 2+h 2) c) g / L d) (g. r 2) / (l. k. G 2)

5) For bifilar suspension ( α / θ ) = _______ a) (g. x. y) / (l. k. G 2) b) (g. h) / (k. G 2+h 2) c) g / L d) (g. r 2) / (l. k. G 2) 6) For bifilar suspension system, the accelerating or disturbing torque is _____ a) m 2 k. G 2α c) mk. G α 2 b) mk. G 2α d) mk. Gα

7) Trifilar suspension system is also called as _____ a) compound pendulum b) bifilar suspension c) torsional pendulum d) none of above 8) In trifilar suspension, the three wires are attached symmetrically w. r. t. axis, the tension in each wire will be ______ of the weight of disc. a) 1 / 2 b) 3 / 4 c) 2 / 5 d) 1 / 3

9) MMI of a spur gear is found by using _____ method. a) simple pendulum b) bifilar suspension c) trifilar suspesion d) compound pendulum 10) MMI of a pulley is found by using _______ method. a) simple pendulum b) bifilar suspension c) trifilar suspesion d) compound pendulum

11) MMI of a disc or flywheel is found by using _____ method a) simple pendulum b) bifilar suspension c) trifilar suspesion d) compound pendulum

12) Frequency of oscillation of compound pendulum does not depend upon a) mass of the body b) material of the body c) size of the body d) all of above Ans : d

13) Which of the following condition should be satisfied by the two-point mass dynamically by the two point mass dynamically equivalent system, when it is replaced by the rigid body? a) m = m 1 + m 2 b) m 1 l 1 = m 2 l 2 c) IG 1 + IG 2 = IG d) all of above 14) ______ is the graphical representation of the crank effort for the different positions of the crank. a) stress – strain diagram b) turning moment c) S - N diagram d) none of the above diagram

15) In case of three cylinder engine, _____ cylinder is the high pressure cylinder. a) first b) second c) third d) all of above 16) In case of three cylinder engine, _____ cylinder is the low pressure cylinder. a) first b) second c) third d) all of above

17) In an IC engine mechanism, the angle turned by crank is 45° from IDC and by connecting rod is 9. 04°. If piston effort is 133. 25 k. N then the force along connecting rod is _____ k. N a) 134. 9 b) 156. 5 c) 182. 8 d) 103. 4 Fq = Fp cos Ø = 133. 25 X cos 9. 04 = 134. 9

18) In an IC engine mechanism, the angle turned by crank is 45° from IDC and by connecting rod is 9. 04°. If piston effort is 133. 25 k. N then the crank effort is ______ k. N a) 134. 9 b) 156. 5 c) 182. 8 d) 109. 2 Fq = Fp cos Ø = 134. 9 Ft = Fq sin (Ɵ+Ø) = 134. 9 X sin(45+9. 04) = 109. 2 k. N

Quiz 3 Unit - 2 TOM I

1) In which of the following application efforts are made to maximize the friction? a) Belt and pulley drive b) Clutches c) Brake d) All of above 2) In which of the following application efforts are made to minimize the friction? a) Machine parts b) Vehicle engine c) Gear drive d) All of above

3) The friction between the nut and bolt is an example of _____ friction. a) sliding b) rolling c) dynamic d) film 4) The force _______ of friction is independent of a) area of contact between the surface b) sliding velocity of one surface over the other c) both of above d) none of above

5) The angle of inclination of the plane , at which the body begins to move down the plane, is called _____ a) angle of friction c) angle of projection b) angle of repose d ) all of above 6) When the journal (shaft) is at rest in the bearing, contact point between the journal and bearing is called as _____ a) friction axis b) friction point c) seat of pressure d) none of above

7) The radius of a friction circle for a shaft of radius r rotating inside a bearing is_______ a) r sinΦ b) r cosΦ c) r tanΦ d) r cotΦ

8) The piston of a steam engine moves with SHM. The crank rotates at 120 rpm with a stroke of 2 meters. Find the velocity and acceleration of piston, when it is at a distance of 0. 75 m from the center. a) 8. 31 m/s , 118. 46 m/s 2 b) 18. 31 m/s , 108. 46 m/s 2 c) 18. 31 m/s , 118. 46 m/s 2 d) 8. 31 m/s , 150. 46 m/s 2 a = ω2. x = 118. 46 m/s 2

9) A uniform slender rod 1. 2 m long is fitted with a transverse pair of knife edges, so that it can swing in a vertical plane as a compound pendulum. The position of knife edge is variable. Find the time of swing of rod if the knife edges are 50 mm from one end of the rod. a) 1. 76 sec b) 2. 54 sec c) 3. 26 sec d) 4. 03 sec K = l/√ 12 = 1. 2/√ 12 = 0. 35 m . . . tp = 1. 76 sec

10) In the above problem, find the time of swing of rod if the knife edges are so placed that time of swing is minimum. a) 2. 68 sec b) 3. 68 sec c) 1. 68 sec d) 4. 68 sec

11) A small connecting rod of mass 1. 5 kg is suspended in a horizontal plane by two wires 1. 25 m long. The wires are attached to the rod at points 120 mm on either side of the centre of gravity. If the rod makes 20 oscillations in 40 sec, find the radius of gyration and the MMI of the rod about a vertical axis through the centre of gravity. a) 207 mm , 0. 017 kg – m 2 b) 107 mm , 0. 017 kg – m 2 c) 407 mm , 0. 117 kg – m 2 d) 107 mm , 0. 217 kg – m 2 fn = 20 / 40 = 0. 5 Hz I = mk 2 = 0. 017 kg-m 2 K = 107 mm

12) In order to find the radius of gyration of a car, it is suspended with its axis vertical from three parallel wires 2. 5 m long. The wires are attached to the rim at points spaced 120° apart and at equal distances 250 mm from axis. It is found that the wheel makes 50 torsional oscillations of small amplitude about its axis in 170 sec. Find the radius of gyration of wheel. a) 268 mm b) 302 mm c) 302 mm 2 d) 268 mm 2 fn = 50 / 170 = 5/17 Hz K = 268 mm

13) A connecting rod of mass 5. 5 kg is placed on a horizontal platform whose mass is 1. 5 kg. It is suspended by three equal wires each 1. 25 m long from a rigid support. The wires are equally spaced round the circumference of circle of 125 mm radius. When the C. G of connecting rod coincides with axis of the circle, the platform makes 10 angular oscillations in 30 sec. Determine the MMI about an axis through its C. G. a) 0. 198 kg-m b) 0. 198 kg-m 2 c) 0. 198 kg/m 2 d) 0. 205 kg-m fn = 10 / 30 = 1/3 Hz K = 0. 168 m I = mk 2 = ( m 1 + m 2 ). k 2 = 0. 198 kg-m 2

14) A shaft of radius 10 cm rotates in a bearing at 800 rpm. If angle of friction is 8. 5° then the diameter of friction circle is _____mm a) 29. 9 b) 38. 1 c) 56. 4 d) 21. 8 Radius of friction circle = r sinΦ = 0. 01 * sin 8. 5 = 0. 0014 Diameter = 0. 0014 * 2 = 0. 00299, m = 29. 9 mm

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