Machine Design Set 17 MCQs

Q1 | The plastic design of steel structures which is based on the statical method of plastic analysis is

independent of safety

gegas no indication of safety

Increasing the diameter of threaded portion

Safe

Unsafe

Q2 | Which is the variable stress

Fluctuating

Reversed

Repeated

Alternating

All of the above

Q3 | Which of the following bearings will have least coefficient of friction?

Tapered bearing

Self-aligning bearing

Cylinder roller bearing

Thrust ball bearing

Single ball bearing

Q4 | A stud has

Counter shunk head

Allen head

Slotted head

Cylindrical head

Both ends threaded

Q5 | The selection of material for gears depends on

Peripheral speed

Type of service

Required dimensions and weight of the drive

Shock and wear resistance

All of the above

Q6 | When large quantities of bolts are to be purchased the quantity is usually specified in terms of

Number

Volume

Packets

Weight

None of the above

Q7 | Both Soderberg and Gerber criteria for failure theories are overly conservative

near the middle of the curves

near the right end of the curves

Increasing the diameter of threaded portion

near the left end of the curves

near the left as well as right ends of the curve

Q8 | Which of the following statement is incorrect?

For columns, the solid round bar is less economical than the turbular section

The radius of gyration for the tubular section in all directions remains the same

A tubular section is most economical for the column free to buckle in any direction

none of the above

Increasing the diameter of threaded portion

Q9 | Coriolis component of acceleration is encountered in

Lower pair

Higher pair

Whit worth-quick-return motion

Four bar mechanism

Mechanism of steam engine

Q10 | Large sections usually have a somewhat lower permissible stress than small sections. This is due to

less homogeneity of structure of material

larger residual stress

greater probability of structural flaws

All of the above

Increasing the diameter of threaded portion

Q11 | The ends of the coil of compression spring which are in contact with the seat are

Carry maximum load

Have significant role in compression

Inactive

Most active

As active as spring

Q12 | Transverse slots are provided on a thread

To reduce effort required to cut threads

For simplicity

For chip removal and lubrication

To reduce stress on threads to be cut

To reduce stress on die

Q13 | Plow bolts are widely used in

electrical fittings

plastics

form machinery

electronic components

Increasing the diameter of threaded portion

Q14 | In case of spur gears, the back lash depends on

Module

Pitch line velocity

Tooth profile

Both (A) and (B) above

None of the above

Q15 | If the threads on a bolt are right hand the threads on nut will be

Right hand with less clearance

Right hand withmore clerance

Left hand with more clearance

Right hand

Left hand

Q16 | Sand drops from the bottom of a hopper into a horizontally moving belt conveyor. If the conveyor is travelling at 2000 fpm and the sand is fed at the rate of 1500 1b/min, the force necessary to drive the conveyor would be

258 lb

Zero

Cannot be determined from the given data

10 kg

516 lb

Q17 | In nylon bearings operate at very high rpm molybdenum disulphide as used mainly to

assists in heat dissipation

provide porous bearing media for vibration absorption

Increasing the diameter of threaded portion

reduce frictional losses

improve mechanical and lubricating properties

Q18 | The pin supporting the exhaust iever of an internal combustion engine is subjected to a shear load of 400 kg/sq-cm the diameter of the pin should be

1.5 cm

4 cm

1 cm

6 cm

2 cm

Q19 | Which of the following is not a standard ball diameter for Brinell hardness testing?

25 mm

1 mm

10 mm

5 mm

2 mm

Q20 | Rivets are made of

Brittle material

Ductile material

Soft material

Hard material

None of the above

Q21 | A rolled steel flat designated as 50 ISF 8 means

the flat is 50 mm wide and 8 mm thick

Increasing the diameter of threaded portion

the flat has cross-section 50 sq. mm and depth 8 mm

the flat has cross-section 50 sq mm and width 8 mm

the flat is 50 mm long and 8 mm thick

Q22 | The loss of strength in compression which occurs when there is a gain in strength in the tension due to overloading is

Bousehinger effect

Relaxation

Hysteresis

Iso-strain

Hooke's effect

Q23 | A spherical gas tank is made of 1 cm steel plate hemispheres but welded together. The tank is 1503 cm in diameter. The allowable internal pressure to which tank may be subjected is the permissible stress be limited to 840 kg/sq cm would be in the range

2.0 to 2.5 kg/sq-cm

3.5 to 5.0 kg/sq-cm

2.5 to 3.5 kg/sq-cm

1.5 to 2.0 kg/sq-cm

1 to 1.5 kg/sq-cm

Q24 | Which type of gears are preferred for low noise applications?

Spur gears with cycloidal profile

Spur gears with involute profile

Bevel gears

Helical gears

Any of the above

Q25 | A screw jack spindle is provided with

Vee threads

BSW threads

Buttress threads

Square threads

None of the above