MECHANISM AND MACHINE MCQ-06

Q.1 Which of the following is governor used in the gramophone ?

A. Pickening

B. Hartnell

C. Porter

D. Centrifugal

Ans-: A

Q.2 Which of the following is not a flexible coupling ?

A. Muff

B. Oldham's 

C. Universal

D. Bushed pin

Ans-: A

Q.3 Practically the sensitiveness of Watt and porter governor are ?

A. Double

B. Half

C. Same

D. 1/3

Ans-: C

Q.4 The pressure angle for involute gears is ___.

A. Depending on type of meshing

B. Depending on size of teeth

C. Variable

D. Always constant

Ans-: D

Q.5 Flank is the surface of gear tooth ________ the pitch surface.

A. Above

B. Below

C. Constant

D. None of the above

Ans-: B

Q.6 Gear box of a car utilises_______.

A. Simple train

B. Complex train

C. Compound train

D. None of the above

Ans-: C

Q.7 Which gears are used for equal speed?

A. Spur gear

B. Bevel gear

C. Mittre gear

D. All of the above

Ans-: C

Q.8 The transverse section of a helical gear is identical to _____.

A. Bevel gear

B. Worm gear

C. Spur gear

D. Mittre gear

Ans-: C

Q.9 The surface of the gear tooth below the pitch surface is called ____.

A. Face

B. Flank

C. Tooth space

D. Tooth thickness

Ans-: B

Q.10 Muff coupling is a ______ coupling.

A. Non- flexible

B. Flexible

C. Semi flexible

D. Hard

Ans-: A

Mechanical governor and types of governor with working principal

GOVERNORS -: 

Governor is a mechanical part of an engine which maintain a constant mean speed of rotation of the crank shaft over long periods during which the load on engine may vary, by controlling the fuel input. Governor supply the fuel to the engine with variation of load on the engine and maintain constant speed.

WORKING PRINCIPAL OF GOVERNOR -:              The mechanical  governors uses the flyweights to create a force based off of the crankshaft speed which is balanced by the force of governor spring. The top engine speed is varied by the increasing spring force to run faster or decreasing the force to run slower. The governor spring wants to open the throttle and governor tries to close the throttle . The interaction of the governor spring and the mechanical governor holds the throttle at the desired engine rpms based upon a force balance and the load or operating conditions.

There are different types of governors -: 

1. Centrifugal governor.                                              2. Inertia governor.                                                      3. Watt governor.                                                        4. Porter governor.                                                      5. Hartnell governor.

1. Centrifugal governor -:                                          In centrifugal governor, governor balls are caused to revolve about the axis of the shaft. For each speed of rotation there is a fixed position of balls when the centrifugal force is just balanced by the inward controlling force exerted by springs. The movement of the balls is transmitted by governor mechanism to control the amount of the  energy supplied to the engine.

2. Inertia governor -:                                                  In this type of governor the balls are so arranged that the inertia force caused by an angular acce- leration or retardation of the governor shaft tend to alter their position and the displacement of the governor balls being controlled by springs. It has rapid response to the effect of a change of load, because displacement of the balls is proportional to the rate of change of speed of rotation.

3. Watt governor -:                                                      The watt governor height is independent of the weight of the balls and length of the supporting arms of the governor. The height of governor is varies inversely as the square of the speed.             Height " h " = g / w^2.      

STRENGTH OF MATERIAL MCQ-10

Q.1 The ratio of number of teeth and pitch circle diameter is called ?

A. Diameteral pitch

B. Pitch

C. Addendum

D. Module

Ans-: A

Q.2 The circle passing through the bottom of the teeth of gear is known as ____.

A. Prime circle

B. Base circle

C. Dedendum circle

D. Addendum circle

Ans-: C

Q.3 The transverse section of a helical gear is identical to the ______ gear.

A. Bevel

B. Worm

C. Spur 

D. Helical

Ans-: C

Q.4 The difference between the addendum and dedendum is known as ______.

A. Backless

B. Clearance

C. Flank

D. Module

Ans-: B

Q.5 The path of contact in involute gears is a____.

A. Curved line

B. Circle

C. Cycloidal 

D. Straight line

Ans-: D

Q.6 Bevel gears are used to transmit ____ motion between two shafts .

A. Reciprocating

B. Rotary

C. Straight line

D. None of the above

Ans-: B

Q.7  Which of the following are spring loaded type governor?

A. Hartnell

B. Proel

C. Gravity

D. All of the above

Ans-: A

Q.8 Which of the following is gravity controlled type governor?

A. Hartnell

B. Watt 

C. Pendulum

D. Porter

Ans-: D

Q.9 A cam and follower constitute ____ pair.

A. Lower

B. Higher

C. Kinematic

D. Link

Ans-: B

Q.10 A joint of two elements permitting relative motion is called ?

A. Lower pair

B. Higher pair

C. Kinematic pair

D. None of the above

Ans-: C

TERMINOLOGY OF GEAR TOOTH

 Terminology of gear tooth 

1.Base circle -: It us the circle from which involute form is generated. only the base circle on a gear is fixed and unalterable.

2.pitch circle -: It us an imaginary circle most use-ful in calculations. It my be noted that an infinite number of pitch circle can be chosen,each asso-ciated with its own pressure angle.

3.Module -: It is defined as the length of the pitch circle diameter per tooth. Thus, if pitch circle diameter of gear be D and number of teeth n, then module (m) = D/n .

4.Pitch circle diameter-: It is the diameter of a circle which by pure rolling action would produce the same motion as the toothed gear wheel. this the most important diameter in gears.

5.Circular pitch -: It the arc distance measured around the pitch circle from the flank of one tooth to a similar flank in the next tooth.

6.Clearance -: This is the radial distance from the tip of a tooth to the bottom of a mating tooth space when the teeth are symmetrically engaged.

7. Diameteral pitch -: The diameteral pitch can be defined as the number of teeth per inch of the pitch circle diameter.

8. Addendum -: Addendum is the radial distance from the pitch circle to the tip of the tooth.

9. Dedendum -: This is the radial distance from the pitch circle to the bottom of tooth space.

Dedendum = Addendum + Clearance 

                    = 1 m + 0.157 m. = 1.157 m

10. Blank diameter -: This is the diameter of the blank from which gear is cut . It is equal to pitch circle diameter plus twice the addenda.

11. Tooth thickness -: The tooth thickness is the arc distance measured along the pitch circle from its intercept with one flank to it's intercept with the other flank of the same tooth.

MECHANISM AND MACHINE MCQ-05

Q.1 In the reciprocating engine Mechanism,the number of links and instantaneous centres are

A. 4 , 5

B. 4 , 6

C. 5 , 4

D. 5 , 6

Ans-: B

Q.2 The number of dead centres in a crank driven slider crank Mechanism are ___.

A. 2

B. 5

C. 4

D. Zero

Ans-: A

Q.3 Base circle decide the size of the ____.

A. Crank

B. Cam

C. Gear

D. Screw

Ans-: B

Q.4 Cylindrical cams can be classified as 

A. Circular

B. Tangent

C. Reciprocating

D. None of the above

Ans-: D

Q.5 Throw of a cam is the maximum distance of follower from ____.

A. Pitch circle

B. Root circle

C. Inner circle

D. Base circle

Ans-: D

Q.6 A circle passing through the pitch point with its centre at the centre of cam axis is known as

A. Base circle

B. Root circle

C. Prime circle

D. None of the above

Ans-: C

Q.7 A watt governor could be classified as the __.

A. Pendulum type governor

B. Dead weight type governor

C. Inertia type governor

D. Centrifugal type governor

Ans-: A

Q.8 Which type of lubricant a rope brake dynamometer uses?

A. Water 

B. Oil

C. Grease

D. No lubricant use

Ans-: D

Q.9 Which type of brake is commonly used on the train Biggie's?

A. Hand brake

B. Shoe brake

C. Electric brake

D. Internal expanding

Ans-: B

Q.10 A Porter governor could be classified as

A. Inertia type governor

B. Pendulum type governor

C. Dead weight type governor

D. None of the above

Ans-: C

MECHANISM AND MACHINE MCQ-04

Q.1 A cam Mechanism imparts _____ motion.

A. Reciprocating

B. Rotating

C. Oscillating

D. All of the above

Ans-: D

Q.2 A kinematic chain requires at least

A. 2 link and 2 turning pair

B. 4 link and 3 turning pair

C. 3 link and 4 turning pair

D. 4 link and 4 turning pair

Ans-: D

Q.3 How many links  Hart Mechanism has ?

A. 6 links

B. 5 links

C. 8 links

D. 1 links

Ans-: A

Q.4 A quarternary joint is equivalent to the _____.

A. One binary joint

B. Two binary joint

C. Three binary joint

D. Four binary joint

Ans-: C

Q.5 The frequency of oscillation at moon compared to earth will be ?

A. 5 times more

B. 2.44 times less

C. 4.2 times more

D. Zero

Ans-: B

Q.6 The main disadvantage of the sliding pair is that it is ____.

A. Wear rapidly

B. Bulky

C. Complicated design

D. A+ B

Ans-: D

Q.7 Which of the following has eight links?

A. Hart Mechanisms

B. Pantograph Mechanism

C. Peaucellier Mechanism

D. None of the above

Ans-: C

Q.8 The approximate straight line Mechanism is a

A. Six bar linkage

B. Four bar linkage

C. Eight bar linkage

D. Two bar linkage

Ans-: B

Q.9 Peaucellier's Mechanism is used to produce mathematically exact _______ motion.

A. Straight line motion

B. Circular line motion

C. Rotating motion

D. None of the above

Ans-: A

Q.10 The part of tooth surface which is above the pitch surface is called?

A. Tooth space

B. Face of the tooth

C. Tooth width

D. None of the above

Ans-: B

MECHANISM AND MACHINE MCQ-03

Q.1 The tendency of a body to resist change from rest or motion is known as___.

A. Inertia

B. Mass

C. Volume

D. Energy

Ans-: A

Q.2 When a ship travels in a sea, which of the effect is more dangerous 

A. Pitching

B. Rolling

C. Steering

D. None of the above

Ans-: A

Q.3 A belt transmitting hourse power is generally dependent upon the ____.

A. Speed of pulley

B. Tension on slack side of belt

C. Tension on tight side of belt

D. Radius of pulley

E. All of the above

Ans-: E

Q.4 In an ideal machine, the output as compared to input is ____.

A. More

B. Less

C. Equal

D. Depending on efficiency

Ans-: C

Q.5 Idler pulley is used for applying ____.

A. Stress

B. Force

C. Power

D. Tension

Ans-: D

Q.6 The indicator using Watt mechanism is known as 

A. Thomson indicator

B. Richard indicator

C. Watt indicator

D. None of the above

Ans-: B

Q.7 The power is transmitted in the automobiles from gear box to differential through the ____.

A. Universal joint

B. Bevel joint

C. Hooke's joint

D. Knuckle joint

Ans-: C

Q.8 A typewriter constitutes ___.

A. Machine

B. Structure

C. Joint

D. Mechanism

Ans-: D

Q.9 The module is equal to ( In a gear drive)

A. 1/ circular pitch

B. 1/ diameteral pitch

C. 2/ diameteral pitch

D. Diameteral pitch/ circular pitch

Ans-: B

Q.10 A pantograph is a Mechanism with the ____.

A. Rolling pair

B. Turning pair

C. Lower pair

D. Higher pair

Ans-: C