ELEMENTS 127-375 Flashcards
- Ackerman steering gear is made up of
a) rolling and sliding pairs
b) rolling pairs
c) sliding and rotary pairs
d) turning pairs
d) turning pairs
- A cam where the follower reciprocates or oscillates in a plane parallel to the axis of the cam is called:
a) circular cam
b) cylindrical cam
c) reciprocating cam
d) tangential cam
b) cylindrical cam
- Instantaneous center of rotation of a link in a four-bar mechanism lies on
a) a point obtained by intersection of extending adjoining links
b) left side pivot of this link
c) right side pivot of this link
d) any of the choices above
a) a point obtained by intersection of extending adjoining links
- A vector quantity that describes both how fast it is moving and the direction in which it is heated.
a) Acceleration
b) Displacement
c) Motion
d) Velocity
d) Velocity
- Which of the following is the rate at which the velocity is changing?
a) Acceleration
b) Linear
c) Motion
d) Vertical
a) Acceleration
- The direction of the __________ is toward the center of the circle in which, the study moves.
a) Centripetal acc.
b) Centrifugal acc.
c) Radial cam
d) Tangential
a) Centripetal acc.
- It is a device that changes the magnitude, direction or mode of application of a torque or force while transmitting it for a particular purpose.
a) Frame
b) Machine
c) Mechanism
d) Structure
b) Machine
- The process of obtaining the resultant of any number of vectors.
a) Scalar quantity
b) Vector composition
c) Vector quantity
d) Vector resolution
b) Vector composition
- It has magnitude, direction and sense.
a) scalar quantity
b) absolute quantity
c) vector quantity
d) relative velocity
c) vector quantity
- A plate, cylinder or other solid with a surface of contact so designed as to caused or modify the motion of the piece.
a) Cam
b) Disc
c) Gear
d) Pulley
a) Cam
- When acceleration is zero, the
a) velocity is constant
b) velocity is negative
c) velocity is variable
d) velocity is zero
a) velocity is constant
- When the velocity is changing, the acceleration is
a) constant
b) not constant
c) variable
d) zero
a) constant
- Klein’s construction is used to determine the
a) acceleration of various parts
b) angular acceleration of various parts
c) displacement of various parts
d) velocity of various parts
a) acceleration of various parts
- Klein’s construction can be used when
a) crank has a uniform angular acceleration
b) crank has a uniform angular velocity
c) crank has a non-uniform angular velocity
d) b and c above
d) b and c above
- The cam angle is
a) the angle subtended by live portion of cam at the cam’s center
b) the angle of rotation of the cam for a definite displacement of the follower
c) the angle subtended at the cam’s center by the portion of cam during which the follower moves
d) the angle subtended by the cam at the cam center when the follower dwells
b) the angle of rotation of the cam for a definite displacement of the follower
- The pitch point on a cam refers to
a) any point on pitch curve
b) a point at a distance equal to pitch circle radius from the center
c) the point of cam pitch circle that has the maximum pressure angle
d) none of the above
c) the point of cam pitch circle that has the maximum pressure angle
- For a kinematics chain to be considered as mechanism,
a) none of the links should be fixed
b) one link should be fixed
c) there is no such criterion
d) two links should be fixed
b) one link should be fixed
- Hart mechanism has how many links?
a) 4
b) 6
c) 8
d) 12
a) 4
- Peaucellier mechanism has how many links?
a) 4
b) 5
c) 6
d) 8
d) 8
- A came with a roller follower would constitute which type of pair?
a) close pair
b) higher pair
c) lower pair
d) open pair
b) higher pair
- Kinematics pairs are those pairs that have
a) elements of pairs not held together mechanically
b) point or line contact between the elements when in motion
c) surface contact between the two elements when in motion
d) two elements that allow relative motion
d) two elements that allow relative motion
- A Pantograph is a mechanism having
a) higher pairs
b) lower pairs
c) rolling pairs
d) spherical pairs
b) lower pairs
- The number of links in a pantograph is equal to
a) 3
b) 4
c) 5
d) 6
b) 4
- In elliptical trammels,
a) all four pairs are turning
b) one pair turning and three pairs sliding
c) three pairs turning and one pair sliding
d) two pairs and two pairs sliding
d) two pairs and two pairs sliding
- The Klein’s method of construction for reciprocating engine mechanism
a) enables determined of Coriolis component
b) is a simplified form of instantaneous
center method
c) is based on acceleration diagram
d) utilizes a quadrilateral similar to the diagram of mechanism for reciprocating engine
d) utilizes a quadrilateral similar to the diagram of mechanism for reciprocating engine
- If a particle of a link has a velocity that changes both in magnitude and direction at any instant, then
a) it must have only unidirectional acceleration
b) it must have two components of acceleration e.g., centripetal and tangential
c) it must have three components of acceleration e.g., centripetal, centrifugal and tangential
d) it must have three components of acceleration e.g., centripetal, centrifugal and gravitational
b) it must have two components of acceleration e.g., centripetal and tangential
- Select the one that is the highest pair.
a) Crosby indicator mechanism
b) Hart’s straight-line mechanism
c) Thomson indicator mechanism
d) Both gearing mechanism
d) Both gearing mechanism
- A shaft revolving in a bearing forms a
a) Cylindrical pair
b) higher pair
c) lower pair
d) sliding pair
c) lower pair
- The total number of instantaneous centers for a mechanism of N links is equal to
a) 2N
b) (N-1) (N+1)
c) 2N(N-1)
d) N(N-1)/2
d) N(N-1)/2
- A kinematics chain needs a minimum of
a) 2 links and 2 turning pairs
b) 3 links and 3 turning pairs
c) 3 links and 2 turning pairs
d) 4 links and 4 turning pairs
d) 4 links and 4 turning pairs
- For kinematics chains formed by lower pair the relation between the number of joint J is given by
a) L=2/3(J+2)
b) L = 3/2(J+2)
c) L = 2/3(L+2)
d) L = 3/2(L+2)
a) L=2/3(J+2)
- In case of an elliptical trammel,
a) one pair turns and two pairs slide
b) two pairs and two pairs slide
c) three pairs turn and one pair slide
d) all four pairs turn
b) two pairs and two pairs slide
- Coriolis component of acceleration is found in
a) four bar mechanisms
b) mechanism of steam engine
c) higher pair
d) Whitworth-quick-return mechanism
d) Whitworth-quick-return mechanism
- It is one that is not appreciably deformed by the action of any external force or load.
a) rigid body
b) structure
c) Frame
d) Mechanism
a) rigid body
- The maximum stress to which a standardized test specimen may be subjected without permanent deformation.
A. Endurance limit
B. Proportional limit
C. Elastic limit
D. Plastic limit
C. Elastic limit
- The modulus of elasticity is a measure of
A. Stiffness
B. Toughness
C. Resilience
D. Hardness
A. Stiffness
- Aging at moderately elevated temperature expedites the process and
A. Natural aging
B. Artificial aging
C. Normal aging
D. Supernatural aging
B. Artificial aging
- It is the tendency to fracture without appreciable deformation
A. Ductility
B. Brittleness
C. Malleability
D. Plasticity
B. Brittleness
- It is the characteristic of exhibiting different properties when tested in different directions
A. Allotropy
B. Anisotropy
C. Isentropic
D. Isotropic
A. Allotropy
- It is one in which specimen, supported at both ends as a simple beam is broken by the impact strength of the metal
A. Charpy test
B. Izod test
C. Rockwell test
D. Universal test
A. Charpy test
- Steel that has been deoxidized with strong deoxidizing agent such as silicon or aluminum, in order to eliminate the reaction between the carbon and oxygen during solidification
A. Carbon steel
B. Tool steel
C. Killed steel
D. Structural steel
C. Killed steel
- Involves the loss of ductility because of a physical or chemical change of the material is known as
A. Embrittlement
B. Pitting
C. Cold shortness
D. Decarburization
A. Embrittlement
- A material commonly used for shielding or screening magnetism
A. Brass
B. Copper
C. Aluminum
D. Soft iron
D. Soft iron
- A magnet is able to attract
A. Iron, aluminum and brass
B. Iron, cobalt and zinc
C. Iron, copper and nickel
D. Nickel, cobalt and steel
D. Nickel, cobalt and steel
- Which of the following materials is used for making permanent magnets?
A. Carbon steel
B. Platinum cobalt
C. Alnico
D. All three mentioned
D. All three mentioned
- Which of the following is the best conductor of electricity?
A. Graphite
B. China clay
C. Porcelain
D. Ceramics
A. Graphite
- Dielectric strength of a material depends on the material’s
A. Moisture content
B. Thickness
C. Temperature
D. All of these
D. All of these
- Which medium has highest value of dielectric strength?
A. Glass
B. Mica
C. Porcelain
D. Quartz
B. Mica
- Which of the following is a primary cell?
A. Mercury – oxide
B. Lead – acid
C. Nickel-iron – alkaline
D. Nickel – cadmium – alkaline
A. Mercury – oxide
- Which of the following contact point metals has highest melting point?
A. Silver
B. Tungsten
C. Gold
D. Copper
C. Gold