MCQOPTIONS
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MCQOPTIONS
This section includes 977 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 351. |
In a differential band brake as shown in the below figure, the drum rotates anticlockwise and the greater tension T₁ acts at A and smaller tension T₂ at B. Length OA is greater than length OB. In order to apply the brake, the force P at C should |
| A. | Be zero |
| B. | Act in upward direction |
| C. | Act in downward direction |
| D. | None of the above |
| Answer» D. None of the above | |
| 352. |
The danger of breakage and vibration is maximum |
| A. | Below the critical speed |
| B. | Near the critical speed |
| C. | Above the critical speed |
| D. | None of these |
| Answer» C. Above the critical speed | |
| 353. |
The contact ratio is given by |
| A. | (Length of the path of approach)/(Circular pitch) |
| B. | (Length of path of recess)/(Circular pitch) |
| C. | (Length of the arc of contact)/(Circular pitch) |
| D. | (Length of the arc of approach)/cosφ |
| Answer» D. (Length of the arc of approach)/cosφ | |
| 354. |
The minimum force required to slide a body of weight W on a rough horizontal plane is |
| A. | W sinθ |
| B. | W cosθ |
| C. | W tanθ |
| D. | W cosecθ |
| Answer» B. W cosθ | |
| 355. |
Typewriter constitutes |
| A. | Machine |
| B. | Structure |
| C. | Mechanism |
| D. | Inversion |
| Answer» D. Inversion | |
| 356. |
In a four stroke I.C. engine, the turning moment during the compression stroke is |
| A. | Positive throughout |
| B. | Negative throughout |
| C. | Positive during major portion of the stroke |
| D. | Negative during major portion of the stroke |
| Answer» C. Positive during major portion of the stroke | |
| 357. |
A kinematic chain requires at least |
| A. | 2 links and 3 turning pairs |
| B. | 3 links and 4 turning pairs |
| C. | 4 links and 4 turning pairs |
| D. | 5 links and 4 turning pairs |
| Answer» D. 5 links and 4 turning pairs | |
| 358. |
If the pressure angle is __________, a reciprocating follower will jam in its bearings. |
| A. | Small |
| B. | Too small |
| C. | Large |
| D. | Too large |
| Answer» E. | |
| 359. |
Governor is used in automobile to |
| A. | Decrease the variation of speed |
| B. | Maximize the fuel economy |
| C. | Limit the vehicle speed |
| D. | Maintain constant engine speed |
| Answer» D. Maintain constant engine speed | |
| 360. |
When the relation between the controlling force (Fc) and radius of rotation (r) for a spring controlled governor is Fc = ar + b, then the governor will be |
| A. | Stable |
| B. | Unstable |
| C. | Isochronous |
| D. | None of these |
| Answer» C. Isochronous | |
| 361. |
In a Hartnell governor, if a spring of greater stiffness is used, then the governor will be |
| A. | Less sensitive |
| B. | More sensitive |
| C. | Unaffected of sensitivity |
| D. | Isochronous |
| Answer» B. More sensitive | |
| 362. |
A spring controlled governor is said to be stable if the controlling force line when produced intersects the Y-axis |
| A. | At the origin |
| B. | Below the origin |
| C. | Above the origin |
| D. | Any one of these |
| Answer» C. Above the origin | |
| 363. |
In order to facilitate starting of locomotive in any position, the cranks of a locomotive with two cylinders, are placed at |
| A. | 45° to each other |
| B. | 90° to each other |
| C. | 120° to each other |
| D. | 180° to each other |
| Answer» C. 120° to each other | |
| 364. |
The displacement of a flat faced follower when it has contact with the flank of a circular arc cam, is given by (where R = Radius of flank, r₁ = Minimum radius of the cam, and θ = Angle turned through by the cam) |
| A. | R (1 - cosθ) |
| B. | (R - r₁) (1 - cosθ) |
| C. | R (1 - sinθ) |
| D. | (R - r₁) (1 - sinθ) |
| Answer» C. R (1 - sinθ) | |
| 365. |
The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because, the |
| A. | Unbalanced couples are caused only at higher speeds |
| B. | Unbalanced forces are not dangerous at higher speeds |
| C. | Effects of unbalances are proportional to the square of the speed |
| D. | Effects of unbalances are directly proportional to the speed |
| Answer» D. Effects of unbalances are directly proportional to the speed | |
| 366. |
Oldham's coupling is the |
| A. | Second inversion of double slider crank chain |
| B. | Third inversion of double slider crank chain |
| C. | Second inversion of single slider crank chain |
| D. | Third inversion of slider crank chain |
| Answer» C. Second inversion of single slider crank chain | |
| 367. |
Which of the following is a turning pair? |
| A. | Piston and cylinder of a reciprocating steam engine |
| B. | Shaft with collars at both ends fitted into a circular hole |
| C. | Lead screw of a lathe with nut |
| D. | Ball and a socket joint |
| Answer» C. Lead screw of a lathe with nut | |
| 368. |
In a flat collar pivot bearing, the moment due to friction is proportional to |
| A. | (r₁² - r₂²)/(r₁ - r₂) |
| B. | (r₁² - r₂²)/(r₁ + r₂) |
| C. | (r₁³ - r₂³)/(r₁² - r₂²) |
| D. | (r₁³ - r₂³)/(r₁ - r₂) |
| Answer» D. (r₁³ - r₂³)/(r₁ - r₂) | |
| 369. |
If ‘D₁’ and ‘D₂’ be the diameters of driver and driven pulleys, then belt speed is proportional to |
| A. | D₁/D₂ |
| B. | D₂/D₁ |
| C. | D₁.D₂ |
| D. | D₁ |
| Answer» E. | |
| 370. |
The velocity of the rubbing surface __________ with the distance from the axis of the bearing. |
| A. | Increases |
| B. | Decreases |
| C. | Remain same |
| D. | None of these |
| Answer» B. Decreases | |
| 371. |
Torsional vibrations are said to occur when the particles of a body moves |
| A. | Perpendicular to its axis |
| B. | Parallel to its axis |
| C. | In a circle about its axis |
| D. | None of these |
| Answer» D. None of these | |
| 372. |
The type of gears used to connect two non parallel and non intersecting shafts is |
| A. | Spur gear |
| B. | Helical gear |
| C. | Bevel gear |
| D. | Spiral gear |
| Answer» E. | |
| 373. |
Which of the following has sliding motion? |
| A. | Crank |
| B. | Connecting rod |
| C. | Crank pin |
| D. | Cross-head |
| Answer» E. | |
| 374. |
The frictional torque transmitted by a disc or plate clutch is same as that of |
| A. | Flat pivot bearing |
| B. | Flat collar bearing |
| C. | Conical pivot bearing |
| D. | Truncated conical pivot bearing |
| Answer» C. Conical pivot bearing | |
| 375. |
The frictional torque transmitted by a cone clutch is same as that of |
| A. | Flat pivot bearing |
| B. | Flat collar bearing |
| C. | Conical pivot bearing |
| D. | Truncated conical pivot bearing |
| Answer» E. | |
| 376. |
In S.H.M., acceleration is proportional to |
| A. | Velocity |
| B. | Displacement |
| C. | Rate of change of velocity |
| D. | All of the above |
| Answer» C. Rate of change of velocity | |
| 377. |
Cam size depends upon |
| A. | Base circle |
| B. | Pitch circle |
| C. | Prime circle |
| D. | Outer circle |
| Answer» B. Pitch circle | |
| 378. |
If there are L number of links in a mechanism, then number of possible inversions is equal to |
| A. | L + 1 |
| B. | L - 1 |
| C. | L |
| D. | L + 2 |
| Answer» D. L + 2 | |
| 379. |
Which one of the following is an exact straight line mechanism using lower pairs? |
| A. | Watt’s mechanism |
| B. | Grasshopper mechanism |
| C. | Robert’s mechanism |
| D. | Peaucellier’s mechanism |
| Answer» E. | |
| 380. |
In a reciprocating engine, usually __________ of the reciprocating masses are balanced. |
| A. | One-half |
| B. | Two-third |
| C. | Three-fourth |
| D. | Whole |
| Answer» C. Three-fourth | |
| 381. |
The effort of a Porter governor is equal to (where c = Percentage increase in speed, m = Mass of ball, and M = Mass on the sleeve) |
| A. | c (m - M) g |
| B. | c (m + M) g |
| C. | c/(m + M) g |
| D. | c/(m - M) g |
| Answer» C. c/(m + M) g | |
| 382. |
For an isochronous Hartnell governor (where r₁ and r₂ = Maximum and minimum radius of rotation of balls respectively, S₁ and S₂ = Maximum and minimum force exerted on the sleeve respectively, and M = Mass on the sleeve) |
| A. | (m.g + S₁)/(m.g + S₂) = r₁/r₂ |
| B. | (m.g - S₁)/(m.g - S₂) = r₂/r₁ |
| C. | S₁/S₂ = r₁/r₂ |
| D. | S₂/S₁ = r₁/r₂ |
| Answer» B. (m.g - S₁)/(m.g - S₂) = r₂/r₁ | |
| 383. |
In S.H.M., the velocity vector w.r.t. displacement vector |
| A. | Leads by 90° |
| B. | Lags by 90° |
| C. | Leads by 180° |
| D. | Are in phase |
| Answer» B. Lags by 90° | |
| 384. |
In a simple harmonic motion, the velocity vector with respect to displacement vector |
| A. | Is in phase |
| B. | Leads by 90° |
| C. | Leads by 180° |
| D. | Lags by 90° |
| Answer» E. | |
| 385. |
The maximum or minimum value of the swaying couple is |
| A. | ± c.m.ω².r |
| B. | ± a (1 - c) m.ω².r |
| C. | ± (a/√2) (1 - c) m.ω².r |
| D. | ± 2a (1 - c) m.ω².r |
| Answer» D. ± 2a (1 - c) m.ω².r | |
| 386. |
The critical speed of a shaft in revolution per second is __________ as that of natural frequency of transverse vibration. |
| A. | Same |
| B. | Different |
| C. | Unpredictable |
| D. | None of these |
| Answer» B. Different | |
| 387. |
For fluctuating loads, well suited bearing is |
| A. | Ball bearing |
| B. | Roller bearing |
| C. | Needle roller bearing |
| D. | Thrust bearing |
| Answer» D. Thrust bearing | |
| 388. |
In vibration isolation system, if ω/ωn > 1, then the phase difference between the transmitted force and the disturbing force is |
| A. | 0° |
| B. | 90° |
| C. | 180° |
| D. | 270° |
| Answer» D. 270° | |
| 389. |
The sense of Coriolis component is such that it |
| A. | Leads the sliding velocity vector by 90° |
| B. | Lags the sliding velocity vector by 90° |
| C. | Is along the sliding velocity vector |
| D. | Leads the sliding velocity vector by 180° |
| Answer» B. Lags the sliding velocity vector by 90° | |
| 390. |
The stress induced in a body will be shear stress, when it is subjected to |
| A. | Longitudinal vibrations |
| B. | Transverse vibrations |
| C. | Torsional vibrations |
| D. | None of these |
| Answer» D. None of these | |
| 391. |
In full depth involute system, the smallest number of teeth in a pinion which meshes with rack without interference is |
| A. | 12 |
| B. | 16 |
| C. | 25 |
| D. | 32 |
| Answer» E. | |
| 392. |
Creep in belt drive is due to |
| A. | Material of the pulley |
| B. | Material of the belt |
| C. | Larger size of the driver pulley |
| D. | Uneven extensions and contractions due to varying tension |
| Answer» E. | |
| 393. |
Transmission angle is the angle between |
| A. | Input link and coupler |
| B. | Input link and fixed link |
| C. | Output link and coupler |
| D. | Output link and fixed link |
| Answer» D. Output link and fixed link | |
| 394. |
Two pulleys of radii r₁ and r₂ and at distance x apart are connected by means of an open belt drive. The length of the belt is |
| A. | π (r₁ + r₂) + (r₁ + r₂)²/x + 2x |
| B. | π (r₁ + r₂) + (r₁ - r₂)²/x + 2x |
| C. | π (r₁ - r₂) + (r₁ - r₂)²/x + 2x |
| D. | π (r₁ - r₂) + (r₁ + r₂)²/x + 2x |
| Answer» C. π (r₁ - r₂) + (r₁ - r₂)²/x + 2x | |
| 395. |
Two pulleys of radii r₁ and r₂ and at distance x apart are connected by means of a cross belt drive. The length of the belt is |
| A. | π (r₁ + r₂) + [(r₁ + r₂)²/x] + 2x |
| B. | π (r₁ + r₂) + [(r₁ - r₂)²/x] + 2x |
| C. | π (r₁ - r₂) + [(r₁ - r₂)²/x] + 2x |
| D. | π (r₁ - r₂) + [(r₁ + r₂)²/x] + 2x |
| Answer» B. π (r₁ + r₂) + [(r₁ - r₂)²/x] + 2x | |
| 396. |
A Porter governor is a |
| A. | Pendulum type governor |
| B. | Dead weight governor |
| C. | Spring loaded governor |
| D. | Inertia governor |
| Answer» C. Spring loaded governor | |
| 397. |
A machine mounted on a single coil spring has a period of free vibration of tp . If the spring is cut into four equal parts and placed in parallel and the machine is mounted on them, then the period of free vibration of the new system will become%! |
| A. | tp /16 |
| B. | tp /4 |
| C. | 4 tp |
| D. | 16 tp |
| Answer» C. 4 tp | |
| 398. |
Balancing of rotating and reciprocating parts of an engine is necessary when it runs at%! |
| A. | Slow speed |
| B. | Moderate speed |
| C. | Highs peed |
| D. | Any one of these |
| Answer» D. Any one of these | |
| 399. |
The magnitude of linear velocity of a point B on a link AB relative to point A is, (Where ω = Angular velocity of the link AB)%! |
| A. | ω × AB |
| B. | ω × (AB)² |
| C. | ω² × AB |
| D. | (ω × AB)² |
| Answer» B. ≈ì√¢ ‚àö√≥ (AB)¬¨‚⧠| |
| 400. |
Which of the following statements regarding laws governing the friction between dry surfaces are correct?%! |
| A. | The friction force is dependent on the materials of the contact surfaces. |
| B. | The friction force is directly proportional to the normal force. |
| C. | The friction force is independent of me area of contact. |
| D. | All of the above |
| Answer» E. | |