MCQOPTIONS
Saved Bookmarks
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.
| 901. |
The design of electromagnets is based upon which of the following fundamental equations ? |
| A. | Force equation |
| B. | Magnetic circuit equation |
| C. | Heating equation |
| D. | Voltage equation |
| E. | All of the above |
| Answer» F. | |
| 902. |
D.C. windings are |
| A. | sometimes 2-layer type |
| B. | never 2-layer type |
| C. | always 2-layer type |
| D. | none of the above |
| Answer» D. none of the above | |
| 903. |
E.m.f. of a Weston cell is accurately measured by |
| A. | electrostatic voltmeter |
| B. | hot wire voltmeter |
| C. | isothermal voltmeter |
| D. | electrodynamic voltmeter |
| Answer» B. hot wire voltmeter | |
| 904. |
In a 3-phase power measurement by two wattmeter method, both the watt meters had identical readings. The power factor of the load was |
| A. | unity |
| B. | 0.8 lagging |
| C. | 0.8 leading |
| D. | zero |
| Answer» B. 0.8 lagging | |
| 905. |
The distance between the starts of two consecutive coils measured in terms of coil sides is called |
| A. | front pitch |
| B. | winding pitch |
| C. | commutator pitch |
| D. | back pitch |
| Answer» C. commutator pitch | |
| 906. |
The heat dissipating capability of transformers of ratings higher than 30 kVA in increased by providing which of the following? |
| A. | Corrugations |
| B. | Fins |
| C. | Tubes |
| D. | All of the above |
| Answer» E. | |
| 907. |
The switch board instruments |
| A. | should be mounted in vertical position |
| B. | should be mounted in horizontal position |
| C. | either (A) or (B) |
| D. | neither (A) nor (B) |
| Answer» B. should be mounted in horizontal position | |
| 908. |
On which of the following variables heat convected depends ? |
| A. | Power density |
| B. | Temperature difference between heated surface and coolant |
| C. | Thermal resistivity, density, specific heat |
| D. | Gravitational constant |
| E. | All of the above |
| Answer» F. | |
| 909. |
In direct cooled system using hydrogen both stator and rotor conductors are made |
| A. | solid |
| B. | hollow |
| C. | perforated |
| D. | any ofthe above |
| Answer» C. perforated | |
| 910. |
By which of the following methods motor rating for variable load drives can be determined ? |
| A. | Method of average losses |
| B. | Equivalent current method |
| C. | Equivalent torque method |
| D. | Equivalent power method |
| E. | All of the above |
| Answer» F. | |
| 911. |
_________ electromagnets generally function as holding magnets. |
| A. | Tractive |
| B. | Portative |
| C. | Either of the above |
| D. | None of the above |
| Answer» C. Either of the above | |
| 912. |
D.C. machines designed with a large value of air gap length have |
| A. | worst, ventilation |
| B. | poor ventilation |
| C. | better ventilation |
| D. | none of the above |
| Answer» D. none of the above | |
| 913. |
When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at |
| A. | shank |
| B. | head |
| C. | in the middle |
| D. | at the thread |
| Answer» E. | |
| 914. |
If an application calls for stresses on screw threads in one direction only, then the following type of thread would be best suited |
| A. | square |
| B. | acme |
| C. | buttress |
| D. | BSW |
| Answer» D. BSW | |
| 915. |
The connecting rod bolts are tightened up with initial tension greater than the external load so that |
| A. | joint may not open up |
| B. | bolts are weakest elements |
| C. | the resultant load on the bolt would not be affected by the external cyclic load |
| D. | bolts will not loosen during service |
| Answer» D. bolts will not loosen during service | |
| 916. |
Allen bolts are |
| A. | self locking bolts |
| B. | designed for shock load |
| C. | used in aircraft application |
| D. | provided with hexagonal depression in head |
| Answer» E. | |
| 917. |
For standard coarse threads of nut, the threads will be as strong in failure by shear as the bolt in tension, if the height of nut (h) is approximately |
| A. | 0.4 times |
| B. | 0.6 times |
| C. | 0.7 times |
| D. | 0.8 times |
| Answer» B. 0.6 times | |
| 918. |
I.S. specifies following total number of grades of tolerances |
| A. | 18 |
| B. | 16 |
| C. | 20 |
| D. | 22 |
| Answer» B. 16 | |
| 919. |
If shearing stress in nut is half the tensile stress in a bolt, then nut length should be equal to |
| A. | diameter of bolt |
| B. | 0.75 x diameter of bolt |
| C. | 1.25 x diameter of bolt |
| D. | 1.5 x diameter of bolt |
| Answer» B. 0.75 x diameter of bolt | |
| 920. |
Whether any core is required in wire ropes |
| A. | yes |
| B. | no |
| C. | sometimes |
| D. | rarely |
| Answer» B. no | |
| 921. |
In cross or regular lay ropes |
| A. | direction of twist of wires in strands is opposite to the direction of twist of strands |
| B. | direction of twist of wires and strands are same |
| C. | all of the above |
| D. | none of the above |
| Answer» B. direction of twist of wires and strands are same | |
| 922. |
Three different weights fall from a certain height under vacuum. They will take |
| A. | same time to reach earth |
| B. | times proportional to weight to reach earth |
| C. | times inversely proportional to weight to reach earth |
| D. | unpredictable |
| Answer» B. times proportional to weight to reach earth | |
| 923. |
In V-belt drive, belt touches |
| A. | at bottom |
| B. | at sides only |
| C. | both at bottom and sides |
| D. | could touch anywhere |
| Answer» C. both at bottom and sides | |
| 924. |
Oil in journal bearing should be applied at the point where load is |
| A. | nil or lightest |
| B. | maximum |
| C. | average |
| D. | all of the above |
| Answer» B. maximum | |
| 925. |
In hydrostatic bearings |
| A. | the Oil film pressure is generated only by the rotation of the journal |
| B. | the oil film is maintained by supplying oil under pressure |
| C. | do not require external supply of lubricant |
| D. | grease is used for lubrication |
| Answer» C. do not require external supply of lubricant | |
| 926. |
The usual clearance provided in hydrodynamic bearing per mm of diameter of shaft is |
| A. | 0.01 micron |
| B. | 0.1 micron |
| C. | 1 micron |
| D. | 10 microns |
| Answer» D. 10 microns | |
| 927. |
In hydrodynamic bearings |
| A. | the oil film pressure is generated only by the rotation of the journal |
| B. | the oil film is maintained by supplying oil under pressure |
| C. | do not require external supply of lubricant |
| D. | grease is used for lubrication |
| Answer» B. the oil film is maintained by supplying oil under pressure | |
| 928. |
If two springs are in parallel then their overall stiffness will be |
| A. | half |
| B. | same |
| C. | double |
| D. | unpredictable |
| Answer» D. unpredictable | |
| 929. |
Aircraft body is usually fabricated by |
| A. | welding |
| B. | precasting |
| C. | rivetting |
| D. | casting |
| Answer» D. casting | |
| 930. |
When a close coiled helical spring is compressed, its wire is subjected to |
| A. | tension |
| B. | shear |
| C. | compression |
| D. | all of the above |
| Answer» B. shear | |
| 931. |
When two springs are in series (having stiffness K), the equivalent stiffness will be |
| A. | K |
| B. | K/2 |
| C. | 2K |
| D. | KIA |
| Answer» C. 2K | |
| 932. |
Spring stiffness is |
| A. | ratio of coil diameter to wire diameter |
| B. | load required to produce unit deflection |
| C. | its capability of storing energy |
| D. | its ability to absorb shocks |
| Answer» C. its capability of storing energy | |
| 933. |
Spring index is |
| A. | ratio of coil diameter to wire diameter |
| B. | load required to produce unit deflection |
| C. | its capability of storing energy |
| D. | indication of quality of spring |
| Answer» B. load required to produce unit deflection | |
| 934. |
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. | |
| 935. |
The piston rod of a steam engine is usually connected to the crosshead by means of |
| A. | bolted joint |
| B. | kunckle joint |
| C. | cotter joint |
| D. | universal joint |
| Answer» D. universal joint | |
| 936. |
When a nut is tightened by plaping a washer below it, the bolt will be subjected to following type of loads |
| A. | compression |
| B. | tension |
| C. | shear |
| D. | combined loads |
| Answer» C. shear | |
| 937. |
Castle nut is a locking device in which |
| A. | one smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming |
| B. | a slot is cut partly is middle of nut and then slot reduced by tightening a screw |
| C. | a hard fiber or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip |
| D. | through slots are made at top and a cotter pin is passed through these and a hole in the bolt, and cotter pin spitted and bent in reverse direction at other end |
| Answer» E. | |
| 938. |
The strap end of a connecting rod of steam engine is joined by |
| A. | gib of cotter joint |
| B. | sleeve and cotter joint |
| C. | spigot socket cotter joint |
| D. | knuckle joint |
| Answer» B. sleeve and cotter joint | |
| 939. |
A tube has the following advantage over pipe |
| A. | lighter and easier to handle |
| B. | greater shock absorption |
| C. | smoother inside walls |
| D. | all of the above |
| Answer» E. | |
| 940. |
In order to permit the thermal expansion/contraction of tubing, it should be |
| A. | crimped |
| B. | honed |
| C. | flared |
| D. | bent |
| Answer» E. | |
| 941. |
The function of cutting oil when threading a pipe is to |
| A. | provide cooling action |
| B. | lubricate the dies |
| C. | help remove chips |
| D. | all of the above |
| Answer» E. | |
| 942. |
Taper on the cotter and slot is provided |
| A. | on both the sides |
| B. | on one side only |
| C. | on none of the sides |
| D. | may be provided anywhere |
| Answer» C. on none of the sides | |
| 943. |
A bench vice has following type of threads |
| A. | metric |
| B. | square |
| C. | buttress |
| D. | acme |
| Answer» E. | |
| 944. |
The draw of cotter need not exceed |
| A. | 3 mm |
| B. | 5 mm |
| C. | 10 mm |
| D. | 20 mm |
| Answer» B. 5 mm | |
| 945. |
Applications in which stresses are encountered in one direction only uses following type of threads |
| A. | metric |
| B. | buttress |
| C. | acme |
| D. | square |
| Answer» C. acme | |
| 946. |
If d is the normal diameter of a bolt in mm, then the initial tension in kg in a bolt used for making a fluid tight joint as for steam engine cover joint is calculated by the relation |
| A. | 102 d |
| B. | 124 d |
| C. | 138 d |
| D. | 168 d |
| Answer» E. | |
| 947. |
Elastic nut is a locking device in which |
| A. | one small nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming |
| B. | a slot is cut partly in middle of nut and then slot reduced by tightening a screw |
| C. | hard fiber or nylon cotter is recessed in the nut and becomes threaded as the nut is stewed on the bolt causing a tight grip |
| D. | through slots are made at top and a cotter-pin is passed through these and a hole in the bolt, and cotter pin splitted and bent in reverse direction at other end |
| Answer» D. through slots are made at top and a cotter-pin is passed through these and a hole in the bolt, and cotter pin splitted and bent in reverse direction at other end | |
| 948. |
Eye bolts are used for |
| A. | foundation purposes |
| B. | locking devices |
| C. | absorbing shock and vibrations |
| D. | lifting and transportation of machines and cubicles. |
| Answer» E. | |
| 949. |
A tapered key which fits in a keyway in the hub and is flat on the shaft, is known as |
| A. | wood-ruff key |
| B. | feather key |
| C. | flat saddle key |
| D. | gib head key |
| Answer» D. gib head key | |
| 950. |
A key made from a cylindrical disc having segmental cross-section, is known as |
| A. | wood-ruff key |
| B. | feather key |
| C. | flat saddle key |
| D. | gib head key |
| Answer» B. feather key | |