MCQOPTIONS
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MCQOPTIONS
This section includes 991 Mcqs, each offering curated multiple-choice questions to sharpen your GATE (Mechanical Engineering) knowledge and support exam preparation. Choose a topic below to get started.
| 151. |
A double fillet welded joint with parallel fillet weld of length l and leg s is subjected to a tensile force P. Assuming uniform stress distribution, the shear stress in the weld is given by |
| A. | √2P/s.l |
| B. | P/2.s.l |
| C. | P/√2.s.l |
| D. | 2P/s.l |
| Answer» D. 2P/s.l | |
| 152. |
Two concentric helical springs used to provide greater spring force are wound is opposite direction. |
| A. | True |
| B. | False |
| C. | Can't say |
| D. | None of these |
| Answer» B. False | |
| 153. |
The fatigue limit of a material is greatly decreased by poor surface conditions. |
| A. | Agree |
| B. | Disagree |
| C. | Can't say |
| D. | None of these |
| Answer» B. Disagree | |
| 154. |
A triple riveted butt joint with double straps of unequal width is to be designed for a boiler shell. The pitch of the rivets in the outer row is double the pitch in the inner row and zig-zag riveting is proposed. Which of the following statement is correct? |
| A. | There are four rivets per pitch length, all in double shear |
| B. | There are four rivets per pitch length, out of which two are in single shear and two are in double shear |
| C. | There are five rivets per pitch length, all in double shear |
| D. | There are five rivets per pitch length, out of which four are in double shear and one is in single shear |
| Answer» E. | |
| 155. |
A pressure vessel is said to be a thin shell, if the ratio of wall thickness to its diameter is equal to 1/10. |
| A. | Yes |
| B. | No |
| C. | Can't say |
| D. | None of these |
| Answer» C. Can't say | |
| 156. |
The malleable material should be plastic but is not essential to be so strong. |
| A. | Agree |
| B. | Disagree |
| C. | Can't say |
| D. | None of these |
| Answer» B. Disagree | |
| 157. |
The antifriction bearings |
| A. | have low starting and low running friction at moderate speeds |
| B. | have high initial cost |
| C. | can carry both radial and thrust loads |
| D. | all of these |
| Answer» E. | |
| 158. |
The toughness of a material __________ when it is heated. |
| A. | increases |
| B. | decreases |
| C. | does not change |
| D. | None of these |
| Answer» C. does not change | |
| 159. |
The number of rivets in shear shall be equal to the number of rivets in crushing. |
| A. | Correct |
| B. | Incorrect |
| C. | Can't say |
| D. | None of these |
| Answer» B. Incorrect | |
| 160. |
The square threads are not so strong as V-threads but they offer less frictional resistance to motion than Whitworth threads. |
| A. | Correct |
| B. | Incorrect |
| C. | Can't say |
| D. | None of these |
| Answer» B. Incorrect | |
| 161. |
The cold working of metals is carried out __________ the recrystallisation temperature. |
| A. | above |
| B. | below |
| C. | Can't say |
| D. | None of these |
| Answer» C. Can't say | |
| 162. |
The spindles of bench vices are usually provided with knuckle threads. |
| A. | Agree |
| B. | Disagree |
| C. | Can't say |
| D. | None of these |
| Answer» C. Can't say | |
| 163. |
A connecting rod subjected to an axial load may buckle in the plane perpendicular to the plane of motion of the connecting rod. |
| A. | Correct |
| B. | Incorrect |
| C. | Can't say |
| D. | None of these |
| Answer» B. Incorrect | |
| 164. |
A bolt of M 24 x 2 means that |
| A. | the pitch of the thread is 24 mm and depth is 2 mm |
| B. | cross-sectional area of the threads is 24 mm² |
| C. | the nominal diameter of bolt is 24 mm and pitch is 2 mm |
| D. | the effective diameter of bolt is 24 mm and there are 2 threads per cm |
| Answer» D. the effective diameter of bolt is 24 mm and there are 2 threads per cm | |
| 165. |
The effect of key ways on a shaft is to reduce its load carrying capacity and to increase its torsional rigidity. |
| A. | True |
| B. | False |
| C. | Can't say |
| D. | None of these |
| Answer» C. Can't say | |
| 166. |
A sliding bearing in which the working surfaces are completely separated from each other by lubricant is called zero film bearing. |
| A. | True |
| B. | False |
| C. | Can't say |
| D. | None of these |
| Answer» C. Can't say | |
| 167. |
For crank shaft bearings, the ratio of the length of the journal to its diameter is less than unity. |
| A. | Correct |
| B. | Incorrect |
| C. | Can't say |
| D. | None of these |
| Answer» B. Incorrect | |
| 168. |
A jam nut is a locking device in which |
| A. | a thinner nut is tightened down over a thicker or main nut and the main nut is tightened against the thinner nut by loosening |
| B. | a slot is cut in line with the centre of each face and a split pin passes through two slots in the nut and a hole in the bolt, so that a positive lock is obtained unless the pin shears |
| C. | a slot is cut about half way through the nut and a small screw is tightened between the nut and the bolt in order to produce more friction |
| D. | the bottom cylindrical portion is recessed to receive the tip of the locking set screw |
| Answer» B. a slot is cut in line with the centre of each face and a split pin passes through two slots in the nut and a hole in the bolt, so that a positive lock is obtained unless the pin shears | |
| 169. |
When percentage of carbon in steel is increased, the ductility of steel decreases. |
| A. | Correct |
| B. | Incorrect |
| C. | Can't say |
| D. | None of these |
| Answer» B. Incorrect | |
| 170. |
In a flange coupling, the thickness of flanges is taken as one-half the diameter of shaft. |
| A. | Agree |
| B. | Disagree |
| C. | Can't say |
| D. | None of these |
| Answer» B. Disagree | |
| 171. |
Which of the following statement is wrong ? |
| A. | The power transmitted by V-belts is less than flat belts for the same coefficient of friction, arc of contact and allowable tension in the belts |
| B. | The V-belt drive is used with large centre distance |
| C. | The V-belt may be operated in either direction with tight side of the belt at the top or bottom |
| D. | The ratio of driving tensions in V-belt drive is more than flat belt drives |
| Answer» C. The V-belt may be operated in either direction with tight side of the belt at the top or bottom | |
| 172. |
Two shafts A and B under pure torsion are of identical length and identical weight and are made of the same material. The shaft A is solid and the shaft B is hollow. We can say that |
| A. | shaft B is better than shaft A |
| B. | shaft A is better than shaft B |
| C. | both the shafts are equally good |
| D. | None of these |
| Answer» B. shaft A is better than shaft B | |
| 173. |
Circumferential joint in boilers is used to get the required length of a boiler. |
| A. | True |
| B. | False |
| C. | Can't say |
| D. | None of these |
| Answer» B. False | |
| 174. |
In order to obtain the bolts of uniform strength, an axial hole is drilled through the head as far as the threaded portion such that the area of shank becomes equal to the root area of the thread. |
| A. | True |
| B. | False |
| C. | Can't say |
| D. | None of these |
| Answer» B. False | |
| 175. |
For unequal width of butt straps, the thickness of butt straps are |
| A. | 0.75 t for wide strap on the inside and 0.625 t for narrow strap on the outside |
| B. | 0.75 t for narrow strap on the inside and 0.625 t for wide strap on the outside |
| C. | 0.75 t for both the straps on the inside and outside |
| D. | 0.625 t for both the straps on the inside and outside |
| Answer» B. 0.75 t for narrow strap on the inside and 0.625 t for wide strap on the outside | |
| 176. |
Which of the following welded joint is designed for shear strength ? |
| A. | Transverse fillet welded joint |
| B. | Parallel fillet welded joint |
| C. | Butt welded joint |
| D. | all of these |
| Answer» C. Butt welded joint | |
| 177. |
A spring of stiffness 1000 N/m is streteched initially by 100 mm from the undeformed position. The work required to stretch it by another 100 mm is |
| A. | 5 N-m |
| B. | 7 N-m |
| C. | 10 N-m |
| D. | 15 N-m |
| Answer» E. | |
| 178. |
The major diameter of a screw thread is also known as core or root diameter. |
| A. | Yes |
| B. | No |
| C. | Can't say |
| D. | None of these |
| Answer» C. Can't say | |
| 179. |
The ratio of driving tensions for flat belts, neglecting centrifugal tension, is (where T1, and T2 = Tensions on the tight and slack sides of belt respectively, μ = Coefficient of friction, between the belt and pulley, and θ = Angle of contact) |
| A. | T₁/T₂ = μθ |
| B. | log (T₁/T₂) = μθ |
| C. | T₁/T₂ =eμθ |
| D. | T₁/T₂ = log μθ |
| Answer» D. T₁/T₂ = log μθ | |
| 180. |
When the bearing is subjected to large fluctuations of load and heavy impacts, the bearing characteristic number should be __________ the bearing modulus. |
| A. | 5 times |
| B. | 10 times |
| C. | 15 times |
| D. | 20 times |
| Answer» D. 20 times | |
| 181. |
According to maximum shear stress theory, the maximum shear stress in the shaft is |
| A. | A |
| B. | B |
| C. | C |
| D. | D |
| Answer» B. B | |
| 182. |
According to Guest's theory, the failure occurs at a point in a member when the maximum shear stress in a bi-axial stress system reaches the shear stress at elastic limit in simple tension test. |
| A. | True |
| B. | False |
| C. | Can't say |
| D. | None of these |
| Answer» B. False | |
| 183. |
The wire ropes make contact at |
| A. | Bottom of groove of the pulley |
| B. | Sides and bottom of groove of the pulley |
| C. | Anywhere in the groove of the pulley |
| D. | Sides of groove of the pulley |
| Answer» B. Sides and bottom of groove of the pulley | |
| 184. |
When a beam of rectangular cross-section of width b and depth d, is subjected to a shear force F, the maximum shear stress induced will be |
| A. | F/bh |
| B. | 3F/2bh |
| C. | 2F/bh |
| D. | 4F/bh |
| Answer» C. 2F/bh | |
| 185. |
When a circular beam of diameter d is subjected to a shear force F, the maximum shear stress induced will be |
| A. | 4F/ πd² |
| B. | 6F/ πd² |
| C. | 8F/ πd² |
| D. | 16F/ 3πd² |
| Answer» E. | |
| 186. |
According to maximum normal stress theory, the maximum normal stress in the shaft is |
| A. | (1/2) × √(σ² × 4τ²) |
| B. | √(σ² × 4τ²) |
| C. | (1/2) × [σ + √(σ² × 4τ²)] |
| D. | σ + √(σ² × 4τ²) |
| Answer» D. σ + √(σ² × 4τ²) | |
| 187. |
In worm gears, the pressure angle is __________ the angle between two inclined faces in axial plane. |
| A. | Half |
| B. | Twice |
| C. | Thrice |
| D. | None of these |
| Answer» B. Twice | |
| 188. |
The expression 0.175 - 0.841/T is the Lewis form factor for |
| A. | 14½° composite and full depth involute system |
| B. | 20° full depth involute system |
| C. | 20° stub system |
| D. | None of the above |
| Answer» D. None of the above | |
| 189. |
Which of the following pipe joints would be suitable for pipes carrying steam? |
| A. | Flanged |
| B. | Threaded |
| C. | Bell and spigot |
| D. | Expansion |
| Answer» E. | |
| 190. |
A machine part subjected to _________ is called a strut. |
| A. | An axial compressive force |
| B. | A tangential force |
| C. | An axial tensile force |
| D. | Any one of these |
| Answer» B. A tangential force | |
| 191. |
Cast iron pipes are mainly used |
| A. | For conveying steam |
| B. | In water and sewage systems |
| C. | In pressure lubrication systems on prime movers |
| D. | All of the above |
| Answer» C. In pressure lubrication systems on prime movers | |
| 192. |
In the levers of third type, the mechanical advantage is __________ one. |
| A. | Less than |
| B. | Equal to |
| C. | More than |
| D. | None of these |
| Answer» B. Equal to | |
| 193. |
In order to withstand resistance to wear, the best profile of gear is |
| A. | 14½° full depth involute tooth |
| B. | 20° full depth involute tooth |
| C. | 20° involute stub tooth |
| D. | 14½° stub tooth |
| Answer» B. 20° full depth involute tooth | |
| 194. |
A compound belt drive is used when |
| A. | Shafts are arranged parallel and rotate in the opposite directions |
| B. | Shafts are arranged parallel and rotate in the same directions |
| C. | Shafts are arranged at right angles and rotate in one definite direction |
| D. | None of the above |
| Answer» E. | |
| 195. |
A fast and loose pulley drive is used when |
| A. | Shafts are arranged parallel and rotate in the opposite directions |
| B. | Shafts are arranged parallel and rotate in the same directions |
| C. | 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 driving shaft |
| Answer» E. | |
| 196. |
An open belt drive is used when |
| A. | Shafts are arranged at right angles and rotate in one definite direction |
| B. | Shafts are arranged parallel and rotate in the opposite directions |
| C. | Shafts are arranged parallel and rotate in the same directions |
| D. | Driven shaft is to be started or stopped whenever desired without interfering with the driving shaft |
| Answer» D. Driven shaft is to be started or stopped whenever desired without interfering with the driving shaft | |
| 197. |
The power transmitted by belt drive depends upon |
| A. | Belt velocity |
| B. | Initial belt tension |
| C. | Arc of contact |
| D. | All of the above |
| Answer» E. | |
| 198. |
The coefficient of friction in belt drive depends upon |
| A. | Material of belt |
| B. | Material of pulley |
| C. | Materials of belt and pulley |
| D. | Belt velocity |
| Answer» D. Belt velocity | |
| 199. |
The bearing characteristic number in a hydrodynamic bearing depends upon |
| A. | Length, width and load |
| B. | Length, width and speed |
| C. | Viscosity, speed and load |
| D. | Viscosity, speed and bearing pressure |
| Answer» E. | |
| 200. |
The design of shafts made of brittle materials is based on |
| A. | Guest's theory |
| B. | Rankine's theory |
| C. | St Venant's theory |
| D. | Von Mises theory |
| Answer» C. St Venant's theory | |