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1. The uniform wear conditions are used_____.((A))For maximum power to be transmitted((B))For safe design of clutches((C))For safe design bearing ((D))For overcoming the frictional torque((E))B2. The uniform Pressure conditions are used_____.((A))For maximum power to be transmitted ((B))For safe design of clutches((C))For safe design bearing ((D))For overcoming the frictional torque((E))C3. For safe design of bearing, we assume____.((A))Maximum power to be transmitted ((B))Safe design of clutches((C)) Safe design bearing ((D)) Overcoming the frictional torque((E))A4. For safe design of clutches, we assume____.((A))Uniform pressure conditions ((B))Uniform wear condition((C))Neither uniform pressure nor uniform wear ((D))All of the above((E))B5. According to uniform wear theory____. Where ,w=Angular velocity of shaft, r=radius of shaft, W=Axial lead on shaft((A))P.w=constant ((B))P.r=constant ((C))P.W=constant ((D))P.T=constant((E))B6. In case of foot step bearing, the frictional force under the conditions of uniform pressure may be assumed to be acting at____.((A))r ((B))(1/2).r ((C))(3/2).r ((D))(2/3)r((E))D7. In case of foot step bearing, the frictional force under the conditions of uniform wear may be assumed to be acting at____.((A))r ((B))(1/2).r ((C))(3/2).r ((D))(2/3).r((E))B8. The ratio of friction torque for uniform pressure to uniform wear for the same dimensions and load is _______.((A))>1 ((B))1 ((C))<1 ((D))(1/2)((E))A9. Torque required to overcome the friction between shaft and bearing surface in case of multiple flat collar bearing is ___________. ((A))Independent on of collars ((B))Dependent on radius of collar((C))Dependent of no of collars ((D))None of above((E))A10. In case of flat pivot bearing,the rubbing velocity is _________.((A))Maximum at the center of the contact area ((B))Zero at the center and maximum at the outer radius ((C))Uniform throughout the contact area ((D))Zero at the outer radius((E))B11. The rate of wearing in case of flat pivot bearing is ______.((A))Inversely proportional to the pressure intensity ((B))Directly proportional to the rubbing velocity((C))Directly proportionl to the pressure intensity ((D))Both (b) and (c )((E))D12. For calculating the friction power for bearing, the assumptions made in practice are_____.((A))The rate of wearing at the surface is uniform ((B))The rubbing velocity is constant ((C))The pressure intensity is uniform ((D))(A) and (C ) only((E))D13. In case of flat pivot bearing the frictional torque transmitted for uniform pressure as compared to the frictional torque transmitted for uniform wear_____.((A))is more ((B))is less ((C))is constant ((D))may be more or less((E))A14. The ratio of friction torque transmitted for uniform pressure to frictional torque transmitted for uniform wear in case of flat pivot, is equal to_______.((A))(1/3) ((B))(2/3) ((C))1 ((D))(4/3)((E))D15. When the axial load carried by the shaft in case of flat collar bearing, is large; a number of collars are provided on the shaft. This is done____.((A))to reduce the frictional torque ((B))to increase the frictional torque((C))to reduce the intensity of pressure ((D))to increse the intensity of pressure((E))C16. Choose the correct statement regarding the safe design of a bearing.((A))When horse power lost in friction is to be determined, uniform rate of wear is assumed((B))When horse power transmitted is to be determined, uniform pressure is assumed((C))When horse power lost in friction is to be determined, uniform pressure is assumed and when horse power transmitted is to be determined, uniform wear is assumed((D))None of the above((E))C17. For uniform pressure the ratio of frictional torque for a flat collar bearing to the frictional torque for conical collar bearing is equal to____. Where ?=semi-angle of the cone((A))1.33 ((B))1 ((C))sin? ((D))cos?((E))C18. For uniform wear, the ratio of frictional torque for a flat collar bearing to the frictional torque for conical collar bearing is equal to____. Where ?=semi-angle of the cone((A))1.33 ((B))1 ((C))sin? ((D))cos?((E))C19. The ratio of frictional torque for a conical collar bearing to that for flat collar bearing is proportional to____. Where ?=semi-angle of the cone((A))sin? ((B))cos? ((C))tan? ((D))1/sin?((E))D20. For flat and conical pivots, the ratio of friction torque with uniform wear to friction torque with uniform pressure is ____.((A))(2/3) ((B))(3/2) ((C))(4/3) ((D))(3/4)((E))D21. The ratio of frictional torque produced for uniform wear to frictional torque produced for uniform pressure is ____.((A))(3/4) ((B))(4/3) ((C))(2/3) ((D))1((E))A22. The frictional torque for the same diameter in a conical bearing is ____.((A))more ((B))less ((C))equal ((D))may be more or less((E))A23. The frictional torque transmitted by a conical bearing is ____.((A))less than that of flat collar bearing ((B))equal to that of flat collar bearing((C))more than that of flat collar bearing ((D))none of the above((E))C24. The frictional torque produced due to friction for same shaft diameter, in conical bearing is____.((A))less than that for flat collar bearing ((B))equal to that for flat collar bearing((C))more than that for flat collar bearing ((D))may be more or less depending upon cone angle((E))C25. Choose the wrong statement((A))The frictional torque transmitted by a shaft fitted with a large number of collars is the same as transmitted by a shaft with one collar((B))The frictional force for uniform pressure, in case of a flat pivot bearing, can be assumed to be acting at a distance of two-thirds of the radius of the shaft from the axis of shaft.((C))When horse power lost in friction is to be determined, uniform pressure is assumed for safe design of bearing((D))The frictional force for uniform pressure, in case of a flat collar pivot bearing, can be assumed to be acting at a distance of half of the sum of internal and external radii of the shaft((E))D26. The ratio of frictional torque produced for uniform wear to that for uniform pressure is ____.((A))1 ((B))(2/3) ((C))(4/3) ((D))(3/4)((E))D27. In case of pivot bearing the rate of wear is _____.((A))Maximum at the center of the contact area ((B))Zero at the center of contact((C))Uniform throughout the contact area ((D))Zero at the maximum radius of the contact area((E))B28. The number of collars are provided to carry a fixed axial force in a flat collar bearing _______.((A))to increase torque ((B))to decrease torque((C))to decrease intensity of pressure ((D))to decrease intensity of pressure((E))C29. In flat pivot bearing the total moment of friction force______.((A))for uniform wear is greater than that for uniform pressure((B))for uniform wear is less than that for uniform pressure((C))for uniform wear is equal to that for uniform pressure((D))for uniform wear may be more or less and cannot be predicted((E))B30. In flat pivot bearing the total power lost in friction ______.((A))for uniform wear is greater than that for uniform pressure((B))for uniform wear is less than that for uniform pressure((C))for uniform wear is equal to that for uniform pressure((D))for uniform wear may be more or less and cannot be predicted31. To be safe side in the design, the unform pressure and uniform wear is assumed respectively_____.((A))for power transmitted by friction and power lost due to friction((B))for power lost due to friction and power transmitted by friction((C))for torque transmitted by friction and friction torque overcome((D))none of the above((E))B32. Choose the correct statement for safe design.((A))for power lost in friction uniform wear is assumed ((B))for power lost in friction uniform pressure is assumed ((C))for power transmitted due to friction uniform pressure is assumed ((D))for power transmitted due to friction or lost in friction uniform wear is assuned((E))B33.Choose the correct statement for safe design.((A))for power transmitted by friction uniform wear is assumed((B))for power transmitted by friction uniform pressure is assumed((C))for power lost in friction and power transmitted uniform wear is assumed ((D))power lost in friction and power transmitted uniform pressure is assuned((E))A34. The purpose of providing multiple collars on a flat collar pivot bearing is to ____.((A))Establish self sustaining bearing conditions ((B))Increase the frictional resistance((C))Distribute the axial load because of limiting bearing pressure on bearing ((D))Increase the power absorbed by the bearing ((E))C35. In a multi-collared thrust bearing consisting of 'n' collars and subjected to axial load W, load sheared by each collar is _______.((A))W ((B))W/n ((C))W/(n-1) ((D))none of these((E))B36. A flat foot step bearing 20 cm in diameter supports a load of 2500 kgf. The shaft is running at 420 rpm and the co-efficient is 0.09. The frictional torque, for uniform pressure, will be equal to ___.((A))11.25 N-m ((B))15 N-m ((C))18.50 N-m ((D))20.0 N-m((E))B37. A flat foot step bearing 20 cm in diameter supports a load of 2500 kgf. The shaft is running at 420 rpm and the co-efficient is 0.09. The frictional torque, for uniform wear, will be equal to ___.((A))11.25 N-m ((B))15 N-m ((C))18.50 N-m ((D))20.0 N-m((E))A38.A flat foot step bearing 20 cm in diameter supports a load of 2500 kgf. The shaft is running at 420 rpm and the co-efficient is 0.09. The power lost in overcoming friction at the bearing, will be equal to ___.((A))650 Watt ((B))880 Watt ((C))659.7 Watt ((D))680.20 Watt((E))C39. flat foot step bearing 20 cm in diameter supports a load of 2500 kgf. The shaft is running at 420 rpm and the co-efficient is 0.09. The power transmitted by the friction between the surface, will be equal to ___.((A))493.875 Watt ((B))880 Watt ((C))659.7 Watt ((D))680.20 Watt((E))A40. A thrust bearing having collars of external and internal diameter as 40 cm and 20 cm respectively, carries an axial load of 3000 N. The co-efficient of friction is 0.09 and shaft runs at 420 rpm. The power lost in friction is to be determined. The corresponding value of friction torque would be ____.((A))40.5 N-m ((B))42 N-m ((C))45.0 N-m ((D))48.5 N-m((E))B41. A thrust bearing having collars of external and internal diameter as 40 cm and 20 cm respectively, carries an axial load of 3000 N. The co-efficient of friction is 0.09 and shaft runs at 420 rpm. The power lost in friction would be equal to ____.((A))1.94 kW ((B))1.84 kW ((C))2 kW ((D))2.5 kW((E))B42. A flat footstep bearing 10 cm radius supports a load of 3 kN. The shaft runs at 600/π r.p.m. and co-efficient of friction is 0.1.The friction torque and frictional power in watts with uniform pressure are respectively.((A))10 N-m and 400 watts ((B))20 N-m and 400 watts ((C))30 N-m and 600 watts ((D))not possible to find for insufficient data((E))B43. A flat footstep bearing 10 cm radius supports a load of 3 kN. The shaft runs at 600/π r.p.m. and co-efficient of friction is 0.1. The friction torque and frictional power in watts with uniform wear are respectively.((A))30 N-m and 600 watt ((B))15 N-m and 300 watts((C))15 N-m and 600 watts ((D))not possible to find for insufficient data((E))B44. A flat foot step bearing 225 mm in diameter supports a load of 7500 N. If the co-efficient of friction is 0.09 and the shaft rotates at 60 rpm, calculate the power lost in frictional torque and frictional power in watts with uniform pressure is ___.((A))50.62 N-m and 317.92 Watt ((B))60.62 N-m and 320.92 Watt((C))57.68 N-m and 321.92 Watt ((D))55.50 N-m and 410.12 Watt((E))A45. Following are the details pertaining to thrust bearing 1) External and internal dia of contacting surfaces-320 mm and 200 mm resp. 2) Axial load-80 kN 3)Pr. Intensity-350 kN/m2 4) shaft speed-400 rpm 5)coefficient of friction-0.06 Calculate power lost in overcoming friction. the frictional torque and power lost in frictional((A))600.35 Nm and 26.60 kW ((B))630.30 Nm and 28.40 kW((C))635.08 Nm and 26.60 kW ((D))650.52 Nm and 27.35 kW((E))C46. A conical pivot supports a load of 20 kN, and its semicone angle is 41.81 degree. The friction coefficient is 0.06 and shaft runs at 200 rpm. The torque required to overcome friction and power lost in friction is((A))135.20 Nm and 2.93 kW ((B))125.40 Nm and 2.93 kW((C))130.35 Nm and 2.53 kW ((D))135.36 Nm and 2.83 kW((E))D47. The clutch is a device used______((A))to absorb frictional torque ((B))to absorb frictional power((C))to transmit power from on shaft to another ((D))all of the above((E))C48. Advantages of positive clutch is_____((A))they can be engaged at high speed ((B))they cause for high speed application((C))shock and noise is there during engagement ((D))due to no slip between contact surfaces no heat is generated((E))D49. Disadvantages of positive clutch is______((A))they can be engaged at high speed ((B))they don’t provide positive engaged((C))shock and noise is there during engagement ((D))due to no slip between contact surfaces no heat is generated((E))C50. Torque transmitted by friction clutch_______((A))is more on the assumption of uniform pressure as compared to uniform wear((B))is less on the assumption of uniform pressure as compared to uniform wear((C))is same on the assumption of uniform pressure and uniform wear((D))is more or less on the assumption of uniform pressure as compared to uniform wear depending upon material((E))A51. For multiple plate clutch having 'n' is the effective number of surfaces for transmitting power then no. of plates are((A))n+1 ((B))n-1 ((C))n ((D))n-2((E))A52. Frictional torque transmission through plate clutch is equivalent to____((A))conical pivot bearing ((B))flat pivot bearing((C))trapezoidal pivot bearing ((D))flat roller bearing((E))D53.In case of cone clutch, power transmission is same as that of________((A))flat pivot bearing ((B))flat collar bearing ((C))trapezoidal pivot bearing ((D))conical pivot bearing((E))C54. Multiple clutch is kind of_________((A))Positive clutch ((B))Cone clutch ((C))Centrifugal clutch ((D))Disc clutch((E))D55. Among which clutch heat dissipation is a serious problem?((A))Multiple clutch ((B))Positive clutch ((C))Cone clutch ((D))Centrifugal clutch((E))A56.In case of clutch , uniform pressure theory is applicable for((A))Old clutch ((B))New clutch ((C))Rusted clutch ((D))Clutch made of hard material((E))B57. Centrifugal clutch are used in _____((A))Truck ((B))Racing car((C))Hack saw((D))Mopeds((E))D58.A friction clutch should be designed on the assumption of((A))uniform wear ((B))uniform pressure ((C))constant friction ((D))any one((E))A59. Considering the safe design, the friction clutch should be designed _______((A))assuming uniform pressure ((B))assuming uniform wear((C))assuming any criteria, either uniform pressure or uniform wear ((D))assuming uniform pressure for high torque and uniform wear for low torque((E))B60. The equivalent coefficient of friction for a cone clutch is ____.((A))? sinα ((B))? tanα ((C))?/sinα ((D))?/tanα((E))C61. Frictional torque transmission through multi plate clutch is equivalent to____.((A))conical pivot bearing ((B))flat pivot bearing ((C))trapezoidal pivot bearing ((D))flat roller bearing((E))D62. In case of multiplate clutch, power transmission is same as that of ______.((A))flat pivot bearing ((B))flat pivot bearing ((C))trapezoidal pivot bearing ((D))conical pivot bearing((E))B63.Single plate clutch is a kind of _________.((A))Positive clutch ((B))Cone clutch ((C))Centrifugal clutch ((D))Disc clutch((E))D64. Which of the following is an example of friction clutch?((A))disc clutch ((B))Cone clutch ((C))Centrifugal clutch ((D))all of the above((E))D65.The frictional torque transmitted by a disc clutch is same as that of _____.((A))flat pivot bearing ((B))flat collar bearing ((C))conical pivot bearing ((D))trapezoidal pivot bearing((E))B66. 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))trapezoidal pivot bearing((E))D67. For safe design, a frictional clutch is designed assuming ____.((A))uniform pressure theory ((B))uniform wear theory ((C))any one of the two ((D))none of the above((E))B68. In multiple friction clutch, the number of active friction surfaces is ____.((A))2n ((B))n ((C))2(n-1) ((D))n-1((E))D69.Friction torque transmitted by a disc or plat clutch is same as that of ____.((A))flat pivot bearing ((B))flat collar bearing ((C))conical pivot bearing ((D))truncated conical pivot bearing((E))B70. For multiple plate friction clutch with n plates, the number of active surfaces n((A))n ((B))n+1 ((C))n-1 ((D))n/2((E)) A71.A single plate clutch is transmitting power, the inner and other radii of the plate are 10 cm and 22.5 cm respectively. Using the radius uniform wear theory, the maximum pressure intensity occurs at a radius of ____.((A))10 cm ((B))15 cm ((C))16.25 cm ((D))22.5 cm((E))A72.Torque transmitted by single plate clutch with axial spring load = 1 kN, and inner and outer radii of 10 cm and 15 cm and ? = 0.5 with assumption of uniform wear is ____.((A))250 N-m ((B))125 N-m ((C))62.5 N-m ((D))not possible to find with given data((E))C73. A multiple clutch with 5 plate transmits torque of 400 N-m. If ? = 0.5 and inner radius = 10 cm and outer radius = 15 cm and four spring expert-axial and load per spring is ___.((A))200 N((B))300 N((C))400 N((D))1280 N((E))C74.Determine the axial force required to engage a cone clutch transmitting 25 kW power at 750 rpm. Average friction diameter of the cone is 400 mm, semicone angle 10 degree and coefficient of friction 0.25. ((A))325.30 Nm and 1100.25 N ((B))318.31 Nm and 1105.47 N((C))320.25 Nm and 1008.20 N ((D))325.89 Nm and 1120.30 N((E))B75.Determine the axial force required to engage a cone clutch transmitting 25 kW power at 750 rpm. Average friction diameter of the cone is 400 mm, semicone angle 60 degree and coefficient of friction 0.25. ((A))325.30 Nm and 1100.25 N ((B))318.31 Nm and 1105.47 N((C))320.25 Nm and 1008.20 N ((D))325.89 Nm and 1120.30 N((E))B76. Brake is a device used for bringing a moving body _____.((A))To rest ((B))To rest retard the motion ((C))To keep it in a state of the rest against the external forces ((D))All of the above ((E))D77.Can simple band brake be made of self-locking type?((A))Yes ((B))Yes, but it will need many modifications ((C))Yes, but with few limitations ((D))NO((E))C78.Material used for brake lining should not have ___.((A))High heat dissipation capacity ((B))Low heat resistance ((C))High strength ((D))High coefficient of friction((E))B79.pivoted block brake is a kind of ____. ((A))Single block brake ((B))Shoe brake ((C))Differential expanding band brake ((D))Internal expanding shoe brake((E))B80.Which type of brakes are used in electric crane?((A))Internal expanding shoe brake ((B))Differential band brake ((C))Single block brake ((D))Double bloke brake((E))D81. In a band brake 'a' is perpendicular distance between slack side and pivot point and 'b' is perpendicular distances between tight side and pivot point. If applied force is downwards then ___.((A))a > b ((B))a = b ((C))a < b ((D))a = b2((E))A82. Brakes used in Railway engine are____.((A))Band brake((B))Internal expending brake ((C))shoe brake((D))Band and block brake((E))C83. The brake commonly used in motor cars ____.((A))shoe brake((B))band brake((C))band and block brake((D))Internal expanding brake((E))D84. When will the distance travelled by 4-wheel be less after braking?((A))applied to rear wheel ((B))when brakes applied to front wheel((C))when brakes applied to all 4-wheels ((D))when brakes applied to rear wheel gradually((E))C85. Brakes are self energizing when____.((A))frictional torque assists the applied torque ((B))frictional torque opposes the applied torque((C))frictional torque vanishes ((D))none of the above((E))B86. In a differential band brake, as shown in fig.1the length OA is greater than OB. In order to apply the brake, the force at C should____.((A))be zero ((B))act in upward direction ((C))act in downward direction ((D))none of the above((E))C87.For the brake to be self locking, the force P at C as shown in fig.1 should____.((A))be zero ((B))act in upward direction ((C))act in downward direction ((D))none of the above((E))A88. When brakes are applied to all the four wheels of a moving car before it is brought to rest, will be____.((A))Maximum ((B))Minimum ((C))Both (a) and (b) ((D))none of the above((E))B89. Which of the following brakes is commonly used in two wheelers?((A))disc brake((B))band brake((C))internal expanding shoe brake((D))(a) and ?((E))D90.Brakes commonly used in trains are _____brakes.((A))band ((B))shoe ((C))band and block ((D))Internal expanding brake((E))B91. In a self locking brake, the force required to apply the brake is_____.((A))minimum ((B))Zero ((C))maximum ((D))none of the above((E))B92. When the frictional force helps the applied force in applying the brake, the brake is____.((A))self locking ((B))automatic ((C))self-energizing ((D))(a) and ?((E))C93.In an internal expanding shoe brake, more than 50% of the total braking torque is supplied by____.((A))leading shoe ((B))trailing shoe ((C))any of the above ((D))none of these((E))A94. Tractive resistance during the propulsion of a wheeled vehicle depends on____.((A))road resistance ((B))aerodynamic resistance b((C))gradient resistance ((D))all of the above((E))D95. A motor car uses____.((A))a band brake ((B))a band and block brake ((C))an external shoe brake ((D))an internally expanding shoe brake((E))D96. For a simple band brake to be effective____.((A))tight side is connected to free end of lever and effort is applied at end so as to move this end away from drum((B))same as (a) above but effort is so applied at end as to move this end towards the drum((C))slack side is connected to the free end of the lever and the effort is applied at end so as to move it away from drum((D))same as ? but effort is applied at end so as to over this end towards the drum((E))D97. For ccw direction of drum rotation in fig.2 brake applied if ____.((A))a>b and P acts downwards ((B))a<b and P acts downwards((C))a=b and P acts downwards ((D))a>b and P acts upwards((E))A98. The band brake in fig.2 will be self-energizing when____.((A))drum rotates ccw and P acts upwards ((B))drum rotates ccw and P acts downwards ((C))drum rotates cw and P acts upwards ((D))drum rotates ccw and P acts downwards((E))D99. Self-locking is not possible in the case of____.((A))simple band brake ((B))Differential band brake ((C))simple block brake ((D))Internal expanding brake((E))A100. A short shoe brake has angle of contact less than____degree.((A))60 ((B))120 ((C))45 ((D))90((E))C101. In block brake, the normal reaction and frictional force act at the mid-point of the block. This is true only if the angle of contact is ____((A))less than 45 degree ((B))less than 60 degree((C))greater than 45 degree ((D))greater than 60 degree((E))A102. In a block brake, when the fulcrum point is below the line of action of friction point, the ratio of effort required for clockwise and counter clockwise rotation is____.((A))equal to 1 ((B))greater than 1 ((C))less than 1 ((D))unpredictable((E))C103. When moment due to friction force aids in applying the brake, it is called____.((A))simple block brake ((B))pivoted block brake ((C))self-locking brake ((D))self-energized brake((E))D104. In a simple band brake, when direction of rotation of drum is changed from counter clockwise direction, the braking torque____.((A))remains unchanged ((B))is increased ((C))is decreased ((D))is unpredictable((E))B105. In a differential band brake, the effort required for clockwise rotation of drum compared to counterclockwise rotation is____.((A))greater ((B))equal ((C))less ((D))unpredictable((E))C106. Refer fig.3 pivot point O2, force at A acting vertically up, then ____.((A))Brake is equally effective in both the directions((B))Brake is more effective in counter-clockwise directions((C))Brake is more effective in clockwise directions((D))Brake is not effective in any direction((E))A107. Refer fig.3 pivot point O1, force at B acting vertically up, then ____.((A))Brake is equally effective in both the directions((B))Brake is more effective in counter-clockwise directions((C))Brake is more effective in clockwise directions((D))Brake is not effective in any direction((E))C108. Refer fig.3 Pivot point O3, force at A vertically up and if ?.d ≥ b then____.((A)) the brake is self-locking in clockwise direction((B)) the brake is self-locking in counter-clockwise direction((C)) the brake is self-locking in both the direction((D)) the brake is not self-locking in any direction((E))B109. Refer fig.3, The best choice for this brake is to have pivot point at____.((A))O1 ((B))O2 ((C))O3 ((D))Anywhere between O3 and A.((E))B110. Refer fig.4. It shows a band brake arrangements. The brake to work with force at A upwards and direction of drum clockwise____.((A))a=b ((B))a>b ((C))a<b ((D))independent of ratio (a/b)((E))C111.Refer Fig. 5 Force downwards and direction counter clockwise________((A))system will work only if a is greater than b ((B))system will not work if a is less than b((C))system will not work if a is equal to b ((D))all the above statements are correct((E))D112. Refer Fig. 5 Force downwards and direction counter clockwise________((A))a/b=T1/T2 gives self-lock ((B))a=0 the brake still works((C))b=0 the brake does not work ((D))all the above statements are correct((E))D113. The stopping distance for a vehicle by applying brakes when all the four wheels are sliding as compared to when all the four wheels are at impending slide is______((A))more ((B))less ((C))same ((D))not predictable((E))A114. For the same co-efficient of friction between the road and the tier and assuming all the wheels at impending slip the stopping distance of vehicle from specified velocity on applying brakes((A))increase with increase of the weight of vehicle ((B))decrease with increase of the weight of vehicle((C))remains same irrespective of the weight of vehicle ((D))is unpredictable((E))C115. A vehicle has weight W and co-efficient of tractive co-efficient μr. It is moving with velocity V when brakes are applied, and all the wheels are at impending slip. The stopping distance Is x. If weight is increased by 50% and μr decreased by 50% then _______ ((A))the stopping distance remains same ((B))the stopping distance increases by 50%((C))the stopping distance decrease by 50% ((D))the stopping distance cannot be determined((E))C116. For same μr and all wheels are impending slip, stopping distance for four wheel vehicle is _____((A))directly proportional to the velocity of vehicle ((B))directly proportional to square of the velocity of the vehicle ((C))directly proportional to weight of vehicle ((D))none of the above((E))B117. The stopping distance for four wheel vehicle is______((A))unaltered by increase for four wheel vehicle ((B))decrease with increase of μr ((C))directly proportional to square of velocity of vehicle ((D))all the above((E))D118.Find the brake power of the engine running at 755 rpm. The length of lever from center of pulley is 1.43 m. The weight in pan is 40 kg.((A))40 kW ((B))42.44 kW ((C))44.36 kW ((D))45.41 kW((E))C119. In a band brake the ratio of tight side band tension to the tension on the slack side is 3. If the angle of band on the drum is 1800 the coefficient of friction required between drum and band is_____((A))0.2 ((B))0.25 ((C))0.3 ((D))0.35((E))D120. A single block brake as shown in Fig.6 has a brake drum diameter of 1m and the angle of contact is 300. It takes 280 Nm torque at 300rpm. The coefficient of friction is 0.35. Determine the required force 'P' to be applied when the rotation of drum is clockwise.((A))378.99 N ((B))420.99 N ((C))435.45 N ((D))450.38 N((E))B121. For above question determine the required force 'P' to be applied when the rotation of drum is anticlockwise.((A))378.99 N ((B))420.99 N ((C))435.45 N ((D))450.38 N((E))A122. A bicycle and rider is mass 125 kg are travelling at speed of 10km/hr. The rider applies a break to the near wheel of 1 m diameter. How far the bicycle will travel before it comes to rest? The pressure applied to the brake is 120 N and μ = 0.05. Also find the number of revolutions made by bicycle before coming to rest.((A))24.58 ((B))25.58((C))23.79 ((D))35.48((E))B123. In a simple band brake applied to a shaft carrying a flywheel of mass 250kg and radius of gyration 350mm , one end of the band is attached to the fulcrum and the other at a distance 300 mm from the fulcrum. The angle embraced by the band is 2250 and the brake drum diameter is 220 mm coefficient of friction 0.25 and the shaft speed is 300 rpm clockwise. Determine the brake torque when a force of 150 N is applied((A))102.99 N ((B))105.24 N ((C))103.26 N ((D))195.38 N((E))C124. A dynamometer is a device used for measuring((A))Power developed by a machine ((B))Torque developed by a machine((C))Power absorbed by a machine ((D))all the above((E))D125.Dynamometer is a device for measuring ____((A))torque exerted by the machine ((B))power developed by the machine((C))power absorbed by the machine ((D))all of the above((E))D126. Which of the following is classified a absorption type of dynamometer?((A))Prony brake dynamometer ((B))Rope brake dynamometer ((C))Hydraulic dynamometer ((D))All of the above((E))D127. Which of the following is classified as transmission type of dynamometer?((A))Prony brake dynamometer ((B))Rope brake dynamometer ((C))Hydraulic dynamometer ((D))Epicyclic Dynamometer((E))D128. Which of the following is an absorption type dynamometer?((A))Prony brake dynamometer ((B))Rope brake dynamometer ((C))Epicyclic-train dynamometer ((D))Both a and b((E))D129. In transmission type of dynamometers, the available power is________((A))Absorbed in overcoming the frictional work ((B))Transmitted except that the small power is absorbed due to friction ((C))Fully transmitted ((D))none of the above((E))B130.An example of an absorption type dynamometer is ___((A))Prony brake dynamometer ((B))Epicyclic Train dynamometer((C))Torsion dynamometer ((D))belt transmission dynamometer((E))A131. An example of a transmission dynamometer is______((A))Prony brake dynamometer ((B))Rope brake dynamometer ((C))Froude dynamometer ((D))Torsion dynamometer((E))D132.Which of the following is classified as absorption dynamometer?((A))Prony brake dynamometer((B))Rope brake dynamometer ((C))Froude's hydraulic dynamometer((D))all of the above((E))C133. Which of the following is classified as transmission dynamometer?((A))Torsion dynamometer((B))Froude's hydraulic dynamometer((C))Belt dynamometer or Tathan dynamometer((D))Prony brake dynamometer((E))C134. In case of dynamometer function of counter weight is to _____((A))Balance the brake when unloaded((B))Adjust pressure on pulley to control speed((C))Prevent rotation of block due to fraction between block and pulley((D))To clamp the blocks((E))A135. Cooling water is used in________((A))Prony brake dynamometer((B))Epicyclic gear train dynamometer((C))Torsion dynamometer((D))Rope brake dynamometer((E))D136. Tathem dynamometer is name given to______((A))Rope brake dynamometer((B))Belt transmission dynamometer((C))Absorption dynamometer((D))Epicyclic Train dynamometer((E))B137. In case of Glibson flash light torsion dynamometer angle of twist can be measured up to _______((A))1/20th of degree((B))1/10th of degree((C))1/70th of degree((D))1/100th of degree((E))D138. The following data refer to a laboratory experiment with rope brake____.Diameter of the flywheel=1m Diameter of the rope = 10mm , Dead weight on the brake = 50kg , Speed of the engine = 200rpm , Spring balance reading = 120N . Find brake power of the engine. ((A))3.91 kW((B))2.90 kW((C))4.90 kW((D))3.80 kW((E))A139. A torsion dynamometer is fitted on turbine shaft to measure the angle of twist. The shaft twist 1.60 for a length of 8 meters at 600 rpm. The diameter of shaft is 250 mm. Find the power transmitted by the turbine. Take G= 80 GPa ((A))68.22 kW((B))67.22 kW((C))65.22 kW((D))66.32 kw((E))B140. The uniform wear conditions are used_____.((A))For maximum power to be transmitted ((B))For safe design of clutches((C))For safe design bearing((D))For overcoming the frictional torque((E))B141. The uniform Pressure conditions are used_____.((A)) For safe design of clutches((B)) For maximum power to be transmitted((C))For safe design bearing((D))For the frictional torque((E))C142. For safe design of bearing, we assume____.((A))Maximum power to be transmitted((B))Safe design of clutches((C)) Safe design bearing((D)) Overcoming the frictional torque((E))A143. For safe design of brakes, we assume____.((A))Uniform pressure conditions((B))Uniform wear condition((C))Neither uniform pressure nor uniform wear((D))All of the above((E))A144.According to uniform wear theory____. Where,w=Angular velocity of shaft, r=radius of shaft, W=Axial lead on shaft((A))Pw=constant((B))Pr=constant ((C)) PT=constant ((D)) PW=constant((E))B145. The uniform wear condition are used__________((A))For maximum power to be transmitted ((B))For safe design of clutches((C))For safe design of bearing((D))For overcoming the frictional torque((E))B146. According to uniform wear theory____. Where, w=Angular velocity of shaft, r=radius of shaft, W=Axial lead on shaft((A))Pw=constant ((B))Pr=constant ((C)) PT=constant ((D)) PW=constant((E))B 147. In case of foot step bearing, the frictional force under the conditions of uniform were may be assumed to be acting at ________.((A))r((B))r/2((C))3r/2 ((D)) 2r/3((E))B148.The ratio of friction torque for uniform pressure to uniform were for the same dimensions and load is _____________.((A))>1((B))=1((C))<1 ((D))=1/2((E))A149. According to uniform wear theory____. Where,w=Angular velocity of shaft, r=radius of shaft, W=Axial lead on shaft((A))Pw=constant((B))Pr=constant((C)) PT=constant ((D)) PW=constant((E))B150.Torque required to overcome the friction between shaft and bearing surface in case of multiple flat collar bearing is ___________.((A)) Independent of no's of collars((B)) Dependent of radius of collars((C)) Dependent of no's of collars ((D)) None of the above((E))A151. According to uniform were theory frictional torque transmitted by conical pivot bearing is ________.((A)) 2/3 (μ W R cosec α)((B)) 1/2 (μ W R cosec α)((C)) 1/2 (μ W R cos α) ((D)) μ W R cosec α((E))B152. Frictional torque as per uniform were theory is __________.((A)) μP (Ro+/Ri)((B)) ? μP (Ro+/Ri)((C)) ? μP [(Ro?+/Ri?)/(Ro?+/Ri?)] ((D)) μP(Ro?-/Ri?)/2 (Ro?-/Ri?)((E))C ................
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