Machine Design 1

Machine design 1271) the design of shafts made of brittle materials is based ona. Guest’s theory b. Rankine’s theoryc. St.Venant’s theory d. Vonmises theory272) A key is normally made from a cold rolled mild steel barsa. right b. wrong 273) Which of the following statement is wrong ?a. a key is used as a temporary fastening b .A key is subjected to tensile stressesc .A key is always inserted parallel to the axis of the shaftd. A key prevents relative motion between the shaft and boss of the pulley274) The taper on a rectangular sunk key is a. 1in 16 b. 1 in 32 c. 1 in 48 d. 1 in 100275) The taper on key is given on a. bottom side only b. top side only c. on both sides d. any side276) The usual proportion for the width of key is a. d/8 b. d/6 c. d/4 d. d/2277) The thickness of key is usually taken equal to one-sixth of diameter of shafta. yes b.no278) A taper key which fits half in the key way of hub and half in the key way of shaft .is known asa. sun key b. flat saddle key c. hollow saddle key d. tangent key279) a hollow saddle key is

a. a taper key which fits half in the key way of hub and half in the key way of shaftb .a taper key which fits in a key way of the hub and is flat on the shaftc. a taper key which fits in a key way of the hub and the bottom of the key is shaped to fit the curved surface of the shaftd. provided in pairs at right angles and each key is to withstand torsion in one direction only280) a tangent key is provided in pairs at right angles and each key is to withstand torsion in one direction onlya. Agree b. disagree281) Which of the following statement is correct?a. A parallel sunk key is a taperless keyb .A parallel sunk key may be rectangular or square in cross-sectionc. A flat saddle key is a taper key which fits in a key way of the hub and is flat on the shaft d. all of the above282) When the pulley or other mating piece is required to slide along the shaft , a ---------- sunk key is useda. rectangular b. square c. parallel283) a feather key transmits a turning moment and permits axial movement alsoa. True b. false284) A key made from a cylindrical disc having segmental cross-section ,is known asa. feather key b. gib-head key c. wood ruff key d. flat saddle key

285) A tapered key which fits in a key way in the hub and is flat on the shaft, is known asa. feather key b. gib-head key c. wood ruff keyd. flat saddle key286) A wood-ruff key isa. a tapered key with head at one endb .fitted in pairs at right anglesc. capable of tilting in a recess milled out in the shaftd. all of the above287) A saddle key ----------- power through frictional resistance onlya. transmits b. does not transmits288) A tapered key which fits in a keyway in the hub and the bottom of which is shaped to fit the curved surface of the shaft, is known as hollow saddle key.a. correct b. incorrect289) A feather key is generallya. loose in shaft and tight in hub b. tight in shaft and loose in hubc. tight in both shaft and hub d. loose in both shaft and hub290) Which of the following key is preferred for the condition when a large amount of impact type torque is to be transmitted in both direction of rotation?a. Woodruff key b. Feather key c. Gib-head key d. Tangent key291) The effect of key ways on a shaft is to reduce its load carrying capacity and to increase its torsional rigiditya. true b. false

292) A key way lowersa. the strength of the shaft b. the rigidity of the shaftc . both the strength and rigidity of the shaftd. the ductility of the shaft293) In a belt drive , if the pulley diameter is doubled keeping the tension and belt width constant .then it will be necessary toa. increase the key length b. increase the key depthc. increase the key width d. decrease the key length294) In the assembly of pulley, key and shafta. pulley is made the weakestb .key is made the weakestc. key is made the strongest d. all the three are designed for equal strength295) The distribution of the forces along the length of key fitted in a shafta. varies linearly b. is uniform throughoutc. varies exponentially ,being more near the torque –input end d. varies exponentially ,being less near the torque –input end296) in designing a key , it is assumed that the distribution of forces along the length of keya. varies linearly b. is uniform throughoutc. varies exponentially .being more at the torque input endd. varies exponentially ,being at the torque input end297) A parallel sunk key, made of steel, is equally strong in shearing and crushing a. yes b. no

298) When the material of key and shaft is same, and the width of key is one-fourth of the diameter of shaft (d) ,then length of key will bea. 0.8 d b. 1.2d c. 1.57d d. 1.8d 299) For a square key made of mild steel ,the shear and crushing strength are related asa. shear strength is equal to crushing strengthb. shear strength is greater than crushing strengthc. shear strength is less than crushing strengthd. none of the above300) Shaft coupling is used in machinery toa. introduce mechanical flexibility b . introduce protection against over loadsc. reduce the transmission of shock loadsd. all of these301) a shaft coupling shoulda. be easy to connect or disconnectb. transmit full power of the shaftc. hold the shafts in perfect alignmentd. all of these302) A coupling used to connect two perfectly aligned shafts, is a. muff coupling b. compression couplingc. flange coupling d. all of these303) which of the following coupling is used to connect two shafts which have both lateral and angular misalignment ?a. Bushed pin type coupling b. Universal coupling c. Oldham coupling d. all of these304) A flange coupling is a type of rigid coupling

a.Right b .wrong305) An universal coupling is a type of ------------ coupling a. rigid b. flexible306) An universal coupling is used to connect two shaftsa. which are perfectly aligned b. which are not in exact alignment c. have lateral misalignment d. whose axes intersect at a small angle307) A flange coupling is used to connect two shaftsa. which are perfectly aligned b. which are not in exact aligned c. have lateral misalignment d. whose axes intersect at a small angle308) a bushed pin flexible coupling is used to connect two shafts whose axes intersect at a small angle a. yes b .no309) Oldham coupling is used to connect two shaftsa. which are perfectly aligned b. which are not perfectly aligned c .which have lateral misalignmentd. whose axes intersect at a small angle310) Oldham coupling is used to transmit power between two parallel shafts which are slightly offseta. True b. false311) The sleeve or muff coupling is designed as aa. thin cylinder b .thick cylinder c .solid shaft d. hollow shaft312) Match Group A with Group BGroup A Group Ba. Oldham coupling a. joins collinear shafts and is of rigidtype b. Flange coupling b. joins non collinearshaftand is adjustable

313) in designing a sleeve coupling, outer diameter of the sleeve is taken asa. d+17 mm b .2d+ 13 mm c. 2d+20 mm d. 3.5dWhere d= diameter of the shaft314) In designing a sleeve coupling , length of the sleeve is taken asa. d+17 mm b.2d+13 mm c. 2d+ 20 mm d. 3.5d315) in a flange coupling ,the keys are staggered at ---------- along the circumference of the shafts in order to divide the weakening effect caused by key waysa. 90 degree b. 135 degree c. 160 degree d. 180 degree316) In a flange coupling ,the flanges are coupled together by means of a. bolts and nuts b. studs c. headless taper boltsd. none of these317) In designing a flange coupling ,the pitch circle diameter of bolts is taken asa. 2d b. 3d c. 4d d. 5d318) For a shaft diameter of 100 mm , the number of bolts in a flange coupling should bea. 4 b. 6 c. 8 d. 10319) For a shaft diameter of 200mm , the number of bolts in a marine flange coupling should bea. 4 b. 6 c. 8 d. 10320) In a flange coupling , the thickness of flange is taken as one-half the diameter of shafta. agree b. disagree

321) In a marine flange coupling , the thickness of flange is taken asa. d/4 b.d/3 c. d/2 d. 3d/4322) In a marine flange coupling , the pitch circle diameter of bolts is taken asa. 1.2d b .1.6d c. 2d d. 2.5d323) a machine part subjected to ------------ is called a struta. an axial tensile force b. an axial compressive forcec. a tangential force d. any one of these324) Slenderness ratio Is the ratio of a. maximum size of column to minimum size of columnb. width of column to depth of columnc. effective length of column to least radius of gyration of the columnd. effective length of column to width of column325) Euler’s formula for a mild steel column is not valid if the slenderness ratio is a. 60 b. 90 c. 100 d. 120326)A column is known as a long column if the slenderness ratio is a. 40 b .50 c. 70 d. 100327) A connecting rod subjected to an axial load may buckle in the plane of motion of the connecting roda. Right b. Wrong328)a connecting rod is designed as aa. long column b. short column c.strut d. all of these329) Which of the following formula is used in designing a connecting rod?

a. Euler’s formula b. Rankine’s formulac .Johnson’s straight line formula d.Johnson’s parabolic formula330) Rankine Gordon formula for buckling is valid fora. long column b. short column c. short and long column d. very long column331) The buckling load will be maximum for a column if a. one end of the column is clamped and the other end is freeb .both ends of the column are clamped c .both ends of the column are hinged d.one end of the column is hinged and the other end is free332) A column of length l is fixed at both ends. The equivalent length of the column isa. l/2 b. l/(2)^1/2c. l d. 2l333) A connecting rod subjected to an axial load may buckle with a. x axis an neutral axis b. Y axis as neutral axisc. X axis or Y axis as neutral axis d. z axis334) A connecting rod subjected to an axial load may buckle in the plane perpendicular to the plane of motion of the connecting roda. correct b. incorrect335) In designing a connecting rod , it is considerable like ---------- for buckling about x axis a. both ends are hinged b. both ends fixed c. one end fixed and the other end hinged d. one end fixed and the other end free

336) in designing a connecting rod, it is considered like -------- for buckling about Y axisa. both ends hinged b. both ends fixed c. One end fixed and the other end hingedd. One end fixed and the other end free337) A connecting rod should bea. strong in buckling about X-axisb .strong in buckling about Y-axisc .equally strong in buckling about X axis and Y axisd.any one of the above338) In order to have a connecting rod equally strong in buckling about x axis and y axis ,the moment of inertia about X axis should be -------- the moment of inertia about Y axisa. equal to b. twice c. three times d. four times339) A connecting rod is four times strong in buckling about Y axis than about X axisa. Agree b. disagree341) In levers, leverage is the ratio of a. load lifted to the effort applied b .mechanical advantage to the velocity ratioc.load arm to the effort arm d. effort arm to the load arm342) When the fulcrum is in between the load and effort , the lever is said to be ofa. first type b. second type c. third type d . any one of above343) in second type of leversa. load is in between the fulcrum and effort b. effort is in between the fulcrum and load

c .fulcrum is in between the load and the effortd.none of these344) When the effort is in between the fulcrum and load , the lever is said to be of third typea. Right b. wrong 345) In the levers of first type , the mechanical advantage is -------- onea. less than b. equal to c. more than346) In levers of --------type ,the mechanical advantage is less than onea. first b. second c. third347) In the levers of third type, the mechanical advantage is ---------- one a. less than b. equal to c. morethan348) The bell crank levers used in railway signaling arrangement are of third type leversA .True b. False349) The rocker arms in internal combustion engines are of first type leversa. correct b .incorrect350) The application of second type levers is found in a. handle of a hand pump b. hand wheel of a punching pressc . lever of a loaded safety valve d. a pair of tongs351) the application of third type levers is found in a. handle of a handpump b. hand wheel of a punching pressc. lever of a loaded safety valve d. a pair of tongs352) the cross-section of the arm of a bell crank lever is

a. rectangular b. elliptical c. I section d. any one of the above353) The design of pin of a rocker arm of an I.C engine is based ona. bearing failure b. shearing failure c. bending failure d. all of these354) Power screws are used to convert rotary motion into translator motiona. True b. false355) Which of the following screw thread is adopted for power transmission in either direction?a. Acme threads b. square threads c . Buttress threads d. multiple threads356) Which of the following screw thread is used for power transmission in one direction onlya. Acme threads b. square threads c. Buttress threads d. Multiple threads357) Multiple threads are used to securea. low efficiency b. high efficiencyc. high load lifting capacity d. high mechanical advantage358) Screws used for power transmission should havea. low efficiency b. high efficiency c. very fine threads d. strong teeth359) Screws jacks have multiple threadsa. agree b. disagree360) The load placed at the top of the screw in a mechanical screw jack is prevented from rotation by providing a swiveling mechanism

a. correct b. incorrect361) When the screw in a mechanical screw jack rotates, the load kept on the top of it movesa. axially upwards b. axially downwardsc .axially upwards or downwards d. none of these364) A screw is said to be self locking screw, if its efficiency is a. less than 50% b. more than 50% c. equal to 50% d. none of these365) A screw is said to be over hauling screw, if its efficiency is a. less than 50% b. more than 50%c. equal to 50% d. none of these366) A screw will be self locking , ifa. friction angle is less than helix angle b .friction angle is more than helix anglec.friction angle is equal to helix angled. efficiency of screw is 100%367) A screw is said to be over hauling screw, if the a.friction angle is less than helix angle b .friction angle is more than helix anglec.friction angle is equal to helix angled. efficiency of screws is 100%368) Which of the following statement is correct regarding power screws?a. The efficiency of a self locking screw can not be more than 50%b. The efficiency of Acme(Trapezoidal) thread is less than that of square thread

c. If the efficiency angle is less than the helix angle of the screw , then the efficiency will be more than 50%d. all of the above369) The load cup of a screw jack is made separate from, the head of the spindle toa. enhance the load carrying capacity of the jackb .reduce the effort needed for lifting the working loadc.prevent the rotation of load being lifted d. reduce the value of frictional torque370) In order to ensure self locking in a screw jack, it is essential that helix angle is ----------- friction anglea. larger than b. smaller than c. equal to371) While designing a screw in a screw jack against buckling failure, the end conditions for the screw are taken as a. both the ends fixed b. both the ends hinged c .one end fixed and the other end hinged d.one end fixed and the other end free372) The power transmitted by means of a belt depends upona. velocity of the beltb. tension under which the belt is placed on the pulleysc .arc of contact between the belt and the smaller pulley373) The V-belt is used to transmit great amount of power and when the two pulleys are very near to each othera. correct b. incorrect374) When the speed of belt increasesa. the coefficient of friction between the belt and pulley increasesb. the coefficient of friction between the belt and pulley

c.the power transmitted will decreased. the power transmitted will increase375) Creep in belt is due toa. material of the beltb. material of the pulleyc. uneven extensions and contractions due to varying tensiond. all of the above376) The coefficient of friction between the belt and pulley depends upon the a. material of belt and pulley b. slip of beltc. speed of belt d. all of these377) an open belt drive is used whena. shafts are arranged parallel and rotate in the opposite directionb .shafts are arranged parallel and rotate in the same directionsc .shafts are arranged at rightangles and rotate in one definite directiond.driven shaft Is to be started or stopped whenever desired without interfering with the driving shaft378) In a crossed belt drive, the shafts are arranged parallel and rotate in the same directiona. right b. wrong 379) a quarter turn belt drives is used when the shafts are arranged at right angles and rotate in onea. yes b .no380) in a belt drive, the velocity ratio is the inverse ratio of the diameters of driving and driven pulleys a. true b. false

381)A compound belt drive is used whena. shafts are arranged parallel and rotate in the opposite directionb .shafts are arranged parallel and rotate in the same directionc .shafts are arranged at right angles and rotate in one definite direction

c. None of the above382) A fast and loose pulley drive is used whena. shafts are arranged parallel and rotate in the opposite directionb. shafts are arranged parallel and rotate in the same directionc .shafts are arranged at right angles and rotate in one definite direction

d. Driven shaft is to be started or stopped whenever desired without interfering with the driven shaft383) The tension on the slack side of the belt is ---------- the tension on the tight side of the belta. equal to b. less than c. greater than384) In a flat belt drive , if the slip between the driver and belt is 1% between the belt and follower is 3% and driver and follower pulley diameters are equal, then velocity ratio of the drive will bea. 0.96 b.0.97 c. 0.98 d. 0.99385) The stretching in a belt can be controlled by ---------- the stress in the belta. reducing b. increasing

387) The power transmitted by a belt drive is maximum when the maxiumum tension in the belt is ----------- the centrifugal tensiona. equal to b. double c. three timesd. six times388) For maximum power , the velocity of the belt will bea. (T/m)^1/2 b. (T/2m)^1/2c. (T/3m)^1/2 d. none of these389) when a belt drive is transmitting maximum powera. effective tension is equal to centrifugal tensionb . effective tension is half of centrifugal tensionc. driving tension on slack side is equal to centrifugal d. driving tension on tight side is twice the centrifugal tension390) All stresses produced in a belt area. compressive stresses b. tensile stressesc. both tensile and compressive stressesd. shear stresses391) The centrifugal tensions in the belt a. increases the power transmittedb. decreases the power transmittedc .has no effect on the power transmittedd.is equal to maximum tension on the belt392) If T1 and T2 are the tension on the tight and slack sides of the belt respectively, and Tc is the centrifugal tension , then initial tension in the belt is equal toa. T1-T2+Tc b. T1+T2+Tc c. (T1-T2+Tc)/2d. (T1+T2+Tc)/2393) In a multiple V-belt drive, if one of the belts break ,then

a. only the broken belt is replaced b.the entire set of belts is replaced c. the broken belt and the belt on either side of it ,is replaced d. the broken belt need not to be replaced394) In a multiple V-belt drive ,when a single belt is damaged ,it is preferable to change the completer set in order toa. reduce vibration b. reduce slipc. ensure uniform loading d. ensure proper alignment395) The steel pulley are -------- in weight than cast iron pulleys of the same capacitya. heavier b. lighter396) The width of the pulley should be --------width of the belta. equal to b. less than c. greater than397) Crowning on pulley helpsa. in decreasing the slip of the belt b .in increasing the slip of the beltc. to keep the belt in centre on a pulley while it is in motiond. to increase pulley life398) Idler pulley is used for a. increasing velocity ratio b. for applying tensionc. changing the direction of motion of belt d. all of these399) the included angle for the V-belt is usuallya. 10 to 20 b. 30 to 40 c. 40 t o60 d. 60 to 80400) In a V-belt drive , the belt makes contact at the bottom of the groove of the pulleya. agree b. disagree