100 IMPORTANT MULTIPLE CHOICE QUESTIONS WITH ANSWERS RELATED TO THEORY OF MACHINES
- The branch of engineering that deals with the study of relative motion between various parts of a machine and the forces acting on them is called:
a) Kinematics
b) Dynamics
c) Mechanism
d) Theory of Machines
Answer: d) Theory of Machines - The point on a link that has zero velocity during its motion is known as:
a) Fixed point
b) Instantaneous center
c) Stationary point
d) Pivot point
Answer: b) Instantaneous center - The number of degrees of freedom for a planar mechanism with n links is:
a) n
b) 2n
c) n-1
d) 2n-3
Answer: d) 2n-3 - The ratio of actual velocity to theoretical velocity is known as:
a) Efficiency
b) Virtual velocity
c) Velocity ratio
d) Mechanical advantage
Answer: c) Velocity ratio - The number of links and degrees of freedom in a four-bar mechanism are respectively:
a) 3, 3
b) 4, 4
c) 4, 2
d) 4, 1
Answer: b) 4, 4 - The Grashof’s criterion is used to determine the possibility of:
a) Rotation of link
b) Relative motion between links
c) Link lengths
d) Link velocities
Answer: b) Relative motion between links - Which of the following mechanisms is used to convert rotary motion into reciprocating motion?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Geneva mechanism
d) Whitworth quick return mechanism
Answer: a) Crank and rocker mechanism - Which of the following mechanisms is used to convert reciprocating motion into rotary motion?
a) Slider-crank mechanism
b) Cam-follower mechanism
c) Oldham’s coupling mechanism
d) Pantograph mechanism
Answer: a) Slider-crank mechanism - The acceleration of a point on a link is maximum when it is:
a) At the midpoint of the link
b) At the start of the link
c) At the end of the link
d) Cannot be determined
Answer: c) At the end of the link - In an involute gear tooth profile, the contact between two teeth occurs at:
a) Pitch point
b) Base circle
c) Addendum circle
d) Dedendum circle
Answer: a) Pitch point - The condition for perfect involute gears is that their pressure angle should be:
a) 45 degrees
b) 20 degrees
c) 30 degrees
d) 15 degrees
Answer: c) 30 degrees - The maximum number of teeth a spur gear can have is limited by:
a) Its pitch diameter
b) Its pressure angle
c) Its face width
d) Its module
Answer: a) Its pitch diameter - The backlash in gears is necessary to:
a) Ensure smooth motion
b) Compensate for manufacturing errors
c) Reduce noise
d) Increase load capacity
Answer: a) Ensure smooth motion - A pair of meshing gears has a gear ratio of 3:1. If the driving gear has 40 teeth, the number of teeth on the driven gear is:
a) 10
b) 20
c) 30
d) 40
Answer: b) 20 - The motion of a slider-crank mechanism can be classified as:
a) Linear motion
b) Rotary motion
c) Oscillatory motion
d) Reciprocating motion
Answer: d) Reciprocating motion - In a four-bar mechanism, if the lengths of two adjacent links are equal, the mechanism is known as a:
a) Grashof mechanism
b) Watt’s mechanism
c) Double-rocker mechanism
d) Parallelogram mechanism
Answer: d) Parallelogram mechanism - The mobility of a mechanism is defined as:
a) The number of links in the mechanism
b) The number of joints in the mechanism
c) The number of degrees of freedom of the mechanism
d) The number of closed loops in the mechanism
Answer: c) The number of degrees of freedom of the mechanism - The length of a polar curve traced by a point on a link of a mechanism is known as:
a) Length of the coupler curve
b) Length of the rocker curve
c) Length of the transmission curve
d) Length of the acceleration curve
Answer: a) Length of the coupler curve - The law of gearing states that the angular velocities of the meshing gears are:
a) Inversely proportional to their number of teeth
b) Directly proportional to their number of teeth
c) Inversely proportional to their radii
d) Directly proportional to their radii
Answer: b) Directly proportional to their number of teeth - A mechanism with 8 links and 12 joints will have ______ degrees of freedom.
a) 8
b) 9
c) 10
d) 12
Answer: b) 9 - The concept of centrifugal force is applied in the analysis of:
a) Statics
b) Dynamics
c) Friction
d) Kinematics
Answer: b) Dynamics - Which of the following is an example of a lower pair?
a) Screw and nut pair
b) Gear pair
c) Cam and follower pair
d) Belt and pulley pair
Answer: a) Screw and nut pair - The Coriolis component of acceleration is always:
a) Radial to the path of motion
b) Tangential to the path of motion
c) Normal to the plane of motion
d) Perpendicular to the path of motion
Answer: b) Tangential to the path of motion - Which of the following mechanisms is used to convert rotary motion into intermittent rotary motion?
a) Geneva mechanism
b) Watt’s mechanism
c) Hooke’s joint mechanism
d) Pantograph mechanism
Answer: a) Geneva mechanism - The minimum number of teeth required for an involute gear is:
a) 12
b) 20
c) 36
d) 50
Answer: a) 12 - In a gear train, the gears are in constant:
a) Angular velocity
b) Linear velocity
c) Acceleration
d) Position
Answer: a) Angular velocity - The property of a cam that determines its shape is known as:
a) Cam lift
b) Cam follower
c) Cam profile
d) Cam rotation
Answer: c) Cam profile - The pitch point of a gear pair is the point of:
a) Maximum velocity
b) Maximum acceleration
c) Tangency between the gears
d) Minimum pressure angle
Answer: c) Tangency between the gears - Which of the following is not a type of gear?
a) Spur gear
b) Helical gear
c) Bevel gear
d) Torsion gear
Answer: d) Torsion gear - A pantograph mechanism is used for:
a) Copying drawings
b) Lifting heavy loads
c) Converting rotary motion into linear motion
d) Changing the direction of motion
Answer: a) Copying drawings - Which of the following mechanisms is used to convert rotary motion into oscillatory motion?
a) Scotch yoke mechanism
b) Oldham’s coupling mechanism
c) Whitworth quick return mechanism
d) Rack and pinion mechanism
Answer: a) Scotch yoke mechanism - The instantaneous center of rotation for a body in pure rolling motion is located:
a) At the point of contact between the body and the surface
b) At the center of mass of the body
c) At the centroid of the body
d) Cannot be determined
Answer: a) At the point of contact between the body and the surface - The equation T = Jα is used to determine the:
a) Torque applied to a body
b) Angular acceleration of a body
c) Linear acceleration of a body
d) Moment of inertia of a body
Answer: a) Torque applied to a body - The mechanism used in clocks to maintain a constant speed of rotation is called a:
a) Pendulum mechanism
b) Escapement mechanism
c) Balance wheel mechanism
d) Flywheel mechanism
Answer: b) Escapement mechanism - Which of the following is an example of a higher pair?
a) Screw and nut pair
b) Gear pair
c) Cam and follower pair
d) Belt and pulley pair
Answer: c) Cam and follower pair - The velocity of a point on a link can be determined by:
a) Instantaneous center method
b) Relative velocity method
c) Virtual center method
d) All of the above
Answer: d) All of the above
- The transmission angle of a four-bar mechanism is defined as the angle between:
a) Input and output links
b) Crank and coupler links
c) Coupler and output links
d) Crank and output links
Answer: b) Crank and coupler links - The total number of links in a single degree of freedom mechanism is:
a) 1
b) 2
c) 3
d) 4
Answer: b) 2 - The velocity of a point on a link is maximum when it is:
a) At the midpoint of the link
b) At the start of the link
c) At the end of the link
d) Cannot be determined
Answer: c) At the end of the link - In a cam-follower mechanism, the follower motion can be classified as:
a) Rotary motion
b) Linear motion
c) Oscillatory motion
d) Reciprocating motion
Answer: b) Linear motion - Which of the following mechanisms is used to convert reciprocating motion into oscillatory motion?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Whitworth quick return mechanism
d) Geneva mechanism
Answer: c) Whitworth quick return mechanism - The pressure angle of a gear tooth profile is the angle between the:
a) Base circle and the tooth profile
b) Pitch circle and the tooth profile
c) Addendum circle and the tooth profile
d) Dedendum circle and the tooth profile
Answer: b) Pitch circle and the tooth profile - Which of the following mechanisms is used to convert rotary motion into linear motion?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Rack and pinion mechanism
d) Geneva mechanism
Answer: c) Rack and pinion mechanism - The condition for perfect involute gears is that their addendum should be:
a) Equal to the dedendum
b) Greater than the dedendum
c) Less than the dedendum
d) Can be equal to or greater than the dedendum
Answer: a) Equal to the dedendum - The maximum efficiency of a machine is always:
a) 100%
b) Less than 100%
c) Greater than 100%
d) Cannot be determined
Answer: b) Less than 100% - Which of the following mechanisms is used to change the direction of motion without changing the speed ratio?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Oldham’s coupling mechanism
d) Geneva mechanism
Answer: c) Oldham’s coupling mechanism - The efficiency of a machine is defined as the ratio of:
a) Output power to input power
b) Input power to output power
c) Mechanical advantage to velocity ratio
d) Velocity ratio to mechanical advantage
Answer: a) Output power to input power - In a four-bar mechanism, if the lengths of all the links are equal, the mechanism is known as a:
a) Grashof mechanism
b) Watt’s mechanism
c) Double-rocker mechanism
d) Parallelogram mechanism
Answer: a) Grashof mechanism - The motion of a point on a link of a mechanism is known as:
a) Linear motion
b) Rotary motion
c) Oscillatory motion
d) Reciprocating motion
Answer: d) Reciprocating motion - Which of the following mechanisms is used to convert linear motion into rotary motion?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Rack and pinion mechanism
d) Geneva mechanism
Answer: b) Scotch yoke mechanism - The law of gearing states that the linear velocities of the meshing gears are:
a) Inversely proportional to their number of teeth
b) Directly proportional to their number of teeth
c) Inversely proportional to their radii
d) Directly proportional to their radii
Answer: d) Directly proportional to their radii - A pair of meshing gears has a gear ratio of 1:3. If the driving gear has 20 teeth, the number of teeth on the driven gear is:
a) 40
b) 60
c) 80
d) 100
Answer: b) 60 - The mobility of a mechanism is always:
a) Less than or equal to the number of links in the mechanism
b) Less than or equal to the number of joints in the mechanism
c) Less than or equal to the number of degrees of freedom of the mechanism
d) Less than or equal to the number of closed loops in the mechanism
Answer: c) Less than or equal to the number of degrees of freedom of the mechanism - The transmission angle of a mechanism is defined as the angle between:
a) Input and output links
b) Crank and coupler links
c) Coupler and output links
d) Crank and output links
Answer: b) Crank and coupler links - The property of a cam that determines its motion is known as:
a) Cam lift
b) Cam follower
c) Cam profile
d) Cam rotation
Answer: a) Cam lift - The pitch circle of a gear is the circle from which the:
a) Tooth profile is derived
b) Pressure angle is measured
c) Addendum and dedendum are determined
d) All of the above
Answer: a) Tooth profile is derived - Which of the following mechanisms is used to convert reciprocating motion into intermittent rotary motion?
a) Geneva mechanism
b) Watt’s mechanism
c) Hooke’s joint mechanism
d) Pantograph mechanism
Answer: a) Geneva mechanism - The minimum number of teeth required for a helical gear is:
a) 10
b) 20
c) 36
d) 50
Answer: c) 36 - The center of curvature of a gear tooth profile is located on the:
a) Pitch circle
b) Base circle
c) Addendum circle
d) Dedendum circle
Answer: b) Base circle - The law of gearing states that the angular velocities of the meshing gears are inversely proportional to their:
a) Number of teeth
b) Pitch diameters
c) Pressure angles
d) Linear velocities
Answer: b) Pitch diameters - In a cam-follower mechanism, the follower motion can be classified as:
a) Rotary motion
b) Linear motion
c) Oscillatory motion
d) Reciprocating motion
Answer: b) Linear motion - The motion of a point on a link can be determined by:
a) Instantaneous center method
b) Relative velocity method
c) Virtual center method
d) All of the above
Answer: d) All of the above - The transmission angle of a four-bar mechanism is defined as the angle between:
a) Input and output links
b) Crank and coupler links
c) Coupler and output links
d) Crank and output links
Answer: b) Crank and coupler links - The total number of links in a mechanism is equal to the sum of:
a) Joints and degrees of freedom
b) Degrees of freedom and closed loops
c) Joints and closed loops
d) Joints, degrees of freedom, and closed loops
Answer: c) Joints and closed loops - The velocity of a point on a link is minimum when it is:
a) At the midpoint of the link
b) At the start of the link
c) At the end of the link
d) Cannot be determined
Answer: a) At the midpoint of the link - Which of the following mechanisms is used to change the direction of motion without changing the speed ratio?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Oldham’s coupling mechanism
d) Geneva mechanism
Answer: c) Oldham’s coupling mechanism - The efficiency of a machine is defined as the ratio of:
a) Output power to input power
b) Input power to output power
c) Mechanical advantage to velocity ratio
d) Velocity ratio to mechanical advantage
Answer: a) Output power to input power - In a four-bar mechanism, if the lengths of all the links are equal, the mechanism is known as a:
a) Grashof mechanism
b) Watt’s mechanism
c) Double-rocker mechanism
d) Parallelogram mechanism
Answer: a) Grashof mechanism - The motion of a point on a link of a mechanism is known as:
a) Linear motion
b) Rotary motion
c) Oscillatory motion
d) Reciprocating motion
Answer: d) Reciprocating motion - Which of the following mechanisms is used to convert linear motion into rotary motion?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Rack and pinion mechanism
d) Geneva mechanism
Answer: b) Scotch yoke mechanism - The law of gearing states that the linear velocities of the meshing gears are:
a) Inversely proportional to their number of teeth
b) Directly proportional to their number of teeth
c) Inversely proportional to their radii
d) Directly proportional to their radii
Answer: d) Directly proportional to their radii - A pair of meshing gears has a gear ratio of 1:4. If the driving gear has 24 teeth, the number of teeth on the driven gear is:
a) 6
b) 8
c) 16
d) 96
Answer: d) 96 - The mobility of a mechanism is always:
a) Less than or equal to the number of links in the mechanism
b) Less than or equal to the number of joints in the mechanism
c) Less than or equal to the number of degrees of freedom of the mechanism
d) Less than or equal to the number of closed loops in the mechanism
Answer: c) Less than or equal to the number of degrees of freedom of the mechanism - The transmission angle of a mechanism is defined as the angle between:
a) Input and output links
b) Crank and coupler links
c) Coupler and output links
d) Crank and output links
Answer: b) Crank and coupler links - The property of a cam that determines its motion is known as:
a) Cam lift
b) Cam follower
c) Cam profile
d) Cam rotation
Answer: a) Cam lift - The pitch circle of a gear is the circle from which the:
a) Tooth profile is derived
b) Pressure angle is measured
c) Addendum and dedendum are determined
d) All of the above
Answer: a) Tooth profile is derived - Which of the following mechanisms is used to convert reciprocating motion into intermittent rotary motion?
a) Geneva mechanism
b) Watt’s mechanism
c) Hooke’s joint mechanism
d) Pantograph mechanism
Answer: a) Geneva mechanism - The minimum number of teeth required for a helical gear is:
a) 10
b) 20
c) 36
d) 50
Answer: c) 36
- The center of curvature of a gear tooth profile is located on the:
a) Pitch circle
b) Base circle
c) Addendum circle
d) Dedendum circle
Answer: b) Base circle - The law of gearing states that the angular velocities of the meshing gears are inversely proportional to their:
a) Number of teeth
b) Pitch diameters
c) Pressure angles
d) Linear velocities
Answer: b) Pitch diameters - In a cam-follower mechanism, the follower motion can be classified as:
a) Rotary motion
b) Linear motion
c) Oscillatory motion
d) Reciprocating motion
Answer: b) Linear motion - The motion of a point on a link can be determined by:
a) Instantaneous center method
b) Relative velocity method
c) Virtual center method
d) All of the above
Answer: d) All of the above - The transmission angle of a four-bar mechanism is defined as the angle between:
a) Input and output links
b) Crank and coupler links
c) Coupler and output links
d) Crank and output links
Answer: b) Crank and coupler links - The total number of links in a mechanism is equal to the sum of:
a) Joints and degrees of freedom
b) Degrees of freedom and closed loops
c) Joints and closed loops
d) Joints, degrees of freedom, and closed loops
Answer: c) Joints and closed loops - The velocity of a point on a link is minimum when it is:
a) At the midpoint of the link
b) At the start of the link
c) At the end of the link
d) Cannot be determined
Answer: a) At the midpoint of the link - Which of the following mechanisms is used to change the direction of motion without changing the speed ratio?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Oldham’s coupling mechanism
d) Geneva mechanism
Answer: c) Oldham’s coupling mechanism - The efficiency of a machine is defined as the ratio of:
a) Output power to input power
b) Input power to output power
c) Mechanical advantage to velocity ratio
d) Velocity ratio to mechanical advantage
Answer: a) Output power to input power - In a four-bar mechanism, if the lengths of all the links are equal, the mechanism is known as a:
a) Grashof mechanism
b) Watt’s mechanism
c) Double-rocker mechanism
d) Parallelogram mechanism
Answer: a) Grashof mechanism - The motion of a point on a link of a mechanism is known as:
a) Linear motion
b) Rotary motion
c) Oscillatory motion
d) Reciprocating motion
Answer: d) Reciprocating motion - Which of the following mechanisms is used to convert linear motion into rotary motion?
a) Crank and rocker mechanism
b) Scotch yoke mechanism
c) Rack and pinion mechanism
d) Geneva mechanism
Answer: b) Scotch yoke mechanism - The law of gearing states that the linear velocities of the meshing gears are:
a) Inversely proportional to their number of teeth
b) Directly proportional to their number of teeth
c) Inversely proportional to their radii
d) Directly proportional to their radii
Answer: d) Directly proportional to their radii - A pair of meshing gears has a gear ratio of 1:5. If the driving gear has 30 teeth, the number of teeth on the driven gear is:
a) 6
b) 7
c) 25
d) 35
Answer: d) 35 - The mobility of a mechanism is always:
a) Less than or equal to the number of links in the mechanism
b) Less than or equal to the number of joints in the mechanism
c) Less than or equal to the number of degrees of freedom of the mechanism
d) Less than or equal to the number of closed loops in the mechanism
Answer: c) Less than or equal to the number of degrees of freedom of the mechanism - The transmission angle of a mechanism is defined as the angle between:
a) Input and output links
b) Crank and coupler links
c) Coupler and output links
d) Crank and output links
Answer: b) Crank and coupler links - The property of a cam that determines its motion is known as:
a) Cam lift
b) Cam follower
c) Cam profile
d) Cam rotation
Answer: a) Cam lift - The pitch circle of a gear is the circle from which the:
a) Tooth profile is derived
b) Pressure angle is measured
c) Addendum and dedendum are determined
d) All of the above
Answer: a) Tooth profile is derived - Which of the following mechanisms is used to convert reciprocating motion into intermittent rotary motion?
a) Geneva mechanism
b) Watt’s mechanism
c) Hooke’s joint mechanism
d) Pantograph mechanism
Answer: a) Geneva mechanism - The minimum number of teeth required for a helical gear is:
a) 10
b) 20
c) 36
d) 50
Answer: c) 36 - The center of curvature of a gear tooth profile is located on the:
a) Pitch circle
b) Base circle
c) Addendum circle
d) Dedendum circle
Answer: b) Base circle - The law of gearing states that the angular velocities of the meshing gears are inversely proportional to their:
a) Number of teeth
b) Pitch diameters
c) Pressure angles
d) Linear velocities
Answer: b) Pitch diameters