McqMate
134
92.9k
190+ Design of Machine Elements Solved MCQs
These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Mechanical Engineering .
| 151. |
If allowable shear stress in the shaft is 70N/mm² and torsional and bending moments are M=1185000N-mm and m=330000N-mm, find the diameter of the shaft. |
| A. | 36.8mm |
| B. | 39.7mm |
| C. | 44.7mm |
| D. | 40.3mm |
| Answer» C. 44.7mm | |
| 152. |
Calculate the shaft diameter on rigidity basis if torsional moment is 196000N-mm, length of shaft is 1000mm. Permissible angle of twist per meter is 0.5’ and take G=79300N/mm². |
| A. | none of the listed |
| B. | 41.2mm |
| C. | 35.8mm |
| D. | 38.8mm |
| Answer» B. 41.2mm | |
| 153. |
The stiffness of solid shaft is more than the stiffness of hollow shaft with same weight. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 154. |
Solid shaft is costlier than hollow shaft of same weight. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 155. |
Flexible shafts have rigidity in torsion making them flexible. |
| A. | low |
| B. | high |
| C. | very high |
| D. | infinitely small |
| Answer» B. high | |
| 156. |
Flexible shafts have rigidity in bending moment. |
| A. | high |
| B. | low |
| C. | very high |
| D. | extremely low |
| Answer» B. low | |
| 157. |
A force 2P is acting on the double transverse fillet weld. Leg of weld is h and length l. Determine the shear stress in a plane inclined at θ with horizontal. |
| A. | psinθ(sinθ+cosθ)/hl |
| B. | p(sinθ+cosθ)/hl |
| C. | pcosθ(sinθ+cosθ)/hl |
| D. | none of the listed |
| Answer» A. psinθ(sinθ+cosθ)/hl | |
| 158. |
Maximum shear stress in transverse fillet weld of leg h and length l is |
| A. | p/hl |
| B. | 1.21p/hl |
| C. | p/1.21hl |
| D. | none of the listed |
| Answer» B. 1.21p/hl | |
| 159. |
Hollow saddle key is superior to flat saddle key as far as power transmitting capability is concerned. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 160. |
Saddle key is more suitable than sunk key for heavy duty applications. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 161. |
The main advantage of sunk key is that it is a drive. |
| A. | positive |
| B. | negative |
| C. | neutral |
| D. | none of the listed |
| Answer» A. positive | |
| 162. |
Woodruff key permits movement b/w shaft and the hub. |
| A. | axial |
| B. | radial |
| C. | eccentric |
| D. | none of the listed |
| Answer» B. radial | |
| 163. |
Determine the length of kennedy key required to transmit 1200N-m and allowable shear in the key is 40N/mm². The diameter of shaft and width of key can be taken as 40mm and 10mm respectively. |
| A. | 49mm |
| B. | 36mm |
| C. | 46mm |
| D. | 53mm |
| Answer» D. 53mm | |
| 164. |
Splines are keys. |
| A. | true |
| B. | false |
| Answer» A. true | |
| 165. |
Refer to fig.
|
| A. | 100n/mm² |
| B. | 50n/mm² |
| C. | 25n/mm² |
| D. | 75n/mm² |
| Answer» B. 50n/mm² | |
| 166. |
Determine the secondary shear stress acting on the bolt 3 and its direction. The bolts are equidistant having separated by 60mm and the margin to the left and right is 25mm.Also P=5kN acts at a distance of 200mm from the channel. |
| A. | 6100n vertically up |
| B. | 4500n vertically down |
| C. | 6100n vertically up |
| D. | 4500n vertically down |
| Answer» C. 6100n vertically up | |
| 167. |
Knuckle Joint can’t be used to connect two intersecting rods. |
| A. | yes |
| B. | no, it can’t be used |
| C. | it can be used with some modificatios |
| D. | it is expensive and hence isn’t used |
| Answer» B. no, it can’t be used | |
| 168. |
A knuckle joint is also called socket pin joint. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 169. |
If knuckle joint is to fail by crushing failure of pin in fork, then determine the diameter of knuckle pin when 50kN axial tensile force act on rods. Given: Max allowable compressive stress=25N/mm², thickness of each eye of fork=25mm. |
| A. | 40mm |
| B. | 50mm |
| C. | 60mm |
| D. | 70mm |
| Answer» A. 40mm | |
| 170. |
Can the cotter joint be used to connect slide spindle and fork of valve mechanism? |
| A. | true |
| B. | false |
| Answer» A. true | |
| 171. |
Among gas and electric arc welding, which has the higher rate of heating? |
| A. | gas welding |
| B. | electric arc welding |
| C. | gas welding and electric arc welding have equal rate of heating |
| D. | cannot be determined |
| Answer» B. electric arc welding | |
| 172. |
Forge welding involves heating of parts to elastic stage and joint is prepared by impact force. |
| A. | yes |
| B. | no, it is done up to plastic stage |
| C. | heating is done up to boiling point |
| D. | none of the listed |
| Answer» B. no, it is done up to plastic stage | |
| 173. |
Which of the following isn’t a main part of rivet? |
| A. | head |
| B. | shank |
| C. | point |
| D. | thread |
| Answer» D. thread | |
| 174. |
In hot riveting the shank portion is subjected to compressive stress. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 175. |
Among punching and drilling, punching is safer. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 176. |
What is the amount of sea coal needed in cast irons for small casting moulding sands? |
| A. | 1% |
| B. | 2% |
| C. | 3% |
| D. | 4% |
| Answer» A. 1% | |
| 177. |
The longest leaf in a leaf spring is called centre leaf. |
| A. | it is called middle leaf |
| B. | it is called master leaf |
| C. | yes |
| D. | none of the listed |
| Answer» B. it is called master leaf | |
| 178. |
If the spring is compressed completely and the adjacent coils touch each other,the the length of spring is called as? |
| A. | solid length |
| B. | compressed length |
| C. | free length |
| D. | none of the mentioned |
| Answer» A. solid length | |
| 179. |
If uncompressed length of spring is 40mm and number of coils 10mm, then pitch of coil is? |
| A. | 4 |
| B. | 40/9 |
| C. | 40/11 |
| D. | none of the mentioned |
| Answer» B. 40/9 | |
| 180. |
Active and inactive, both types of coils support the load although both don’t participate in spring action. |
| A. | active coils don’t support the load |
| B. | inactive coils don’t support the load |
| C. | both active and inactive don’t support the load |
| D. | both active and inactive support the load |
| Answer» B. inactive coils don’t support the load | |
| 181. |
The coefficient of fluctuation of speed is the of maximum fluctuation of speed and the mean speed. |
| A. | product |
| B. | ratio |
| C. | sum |
| D. | difference |
| Answer» B. ratio | |
| 182. |
If E = Mean kinetic energy of the flywheel, CS = Coefficient of fluctuation of speed and Δ E = Maximum fluctuation of energy, then |
| A. | Δe = e / cs |
| B. | Δe = e2 × cs |
| C. | topic 4.2 flywheels considering stresses in rims and arms for engines and punching machines |
| Answer» B. Δe = e2 × cs | |
| 183. |
The tensile stress in the flywheel rim due to the centrifugal force acting on the rim is given by |
| A. | ρ v2/4 |
| B. | ρ v2/2 |
| C. | 3ρ v2/4 |
| D. | ρ v2 |
| Answer» D. ρ v2 | |
| 184. |
In a four stroke cycle engine camshaft revolves at the crank speed. |
| A. | two times |
| B. | half |
| C. | four times |
| D. | three times |
| Answer» B. half | |
| 185. |
Crankshafts are usually constructed by |
| A. | casting |
| B. | drop forging |
| C. | drawing |
| D. | extrusion |
| Answer» B. drop forging | |
| 186. |
A bearing supports the load acting along the axis of the shaft. |
| A. | thrust |
| B. | radial |
| C. | longitudinal |
| D. | transversal |
| Answer» A. thrust | |
| 187. |
In steam and gas turbines, rolling contact bearings are used. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 188. |
Deep groove ball bearings creates a lot of noise. |
| A. | yes |
| B. | they create very less noise |
| C. | depends on the application |
| D. | no reference frame for comparison is mentioned |
| Answer» B. they create very less noise | |
| 189. |
In angular contact bearings, bearings are required to take thrust load in both directions. |
| A. | 1 |
| B. | 4 |
| C. | 2 |
| D. | 3 |
| Answer» C. 2 | |
| 190. |
Which of the following isn’t the property of taper roller? |
| A. | high rigidity |
| B. | easy dismantling |
| C. | take low radial and heavy loads |
| D. | all are the properties of tapper roller |
| Answer» C. take low radial and heavy loads | |
| 191. |
Which of the following cannot take radial load? |
| A. | cylindrical roller bearing |
| B. | taper roller bearing |
| C. | thrust ball bearing |
| D. | none of the listed |
| Answer» C. thrust ball bearing | |
| 192. |
There are common types of bevel gears. |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» B. 2 | |
| 193. |
Miter gears are the bevel gears mounted on shaft which are intersecting at angle greater than 90. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 194. |
In hypoid bevel gears, shafts may continue past each other. |
| A. | true |
| B. | false |
| Answer» A. true | |
| 195. |
Hypoid gears have the following characteristics. |
| A. | curved teeth |
| B. | mounted on non -parallel non intersecting shafts |
| C. | efficiency of 97% |
| D. | all of the mentioned |
| Answer» D. all of the mentioned | |
| 196. |
The bearing characteristic number shown in the graph is directly proportional to the unit bearing pressure. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 197. |
A single transverse weld is preferred over double transverse fillet weld. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 198. |
5 SELECTION OF ROLLING CONTACT BEARINGS |
| A. | thrust |
| B. | radial |
| C. | longitudinal |
| D. | transversal |
| Answer» A. thrust | |
Done Studing? Take A Test.
Great job completing your study session! Now it's time to put your knowledge to the test. Challenge yourself, see how much you've learned, and identify areas for improvement. Don’t worry, this is all part of the journey to mastery. Ready for the next step? Take a quiz to solidify what you've just studied.