Theory of Machines – Questions and Answers

Theory of Machines Questions and Answers

1-In order to have a complete balance of the several revolving masses in different planes

(A) The resultant couple must be zero

(B) The resultant force must be zero

(C) Both the resultant force and resultant couple must be zero

(D) None of the above


2-A flywheel is a device which controls

(A) the mean speed of rotation of the engine shaft over a long period of time

(B) the speed variation caused by cyclic fluctuation of energy

(C) the fluctuation of energy over a long period

(D) the fuel supply to control the mean speed of the engine shaft


3-Identify the antifriction bearing

(A) Ball and roller bearing

(B) Thrust bearing

(C) Journal bearing

(D) Gas bearing


4-Types of gears used to connect two non-parallel non-intersecting shafts are

(A) Spur gears

(B) Bevel gears

(C) Helical gears

(D) Spiral gears


5-In a gear train, when the axes of the shafts over which gears are mounted, move relative to a fixed axis, is called

(A) Simple gear train

(B) Compound gear train

(C) Reverted gear train

(D) Epicyclic gear train


6-In a spur gear the product of diametral pitch and circular pitch is equal to

(A) 1/π

(B) 1

(C) 2π

(D) π


7-The following one is an inversion of single slider crank chain

(A) Watt’s indicator mechanism

(B) Beam engine

(C) Whitworth quick return motion mechanism

(D) Elliptical trammel


8-A kinematic chain has ‘n’ links. The number of possible inversions is

(A) n

(B) (n-1)

(C) n+1

(D) (n-2)

9-If the elements in a kinematic pair have line contact or point contact. When in motion, the pair is called.

(A) Lower pair

(B) Higher pair

(C) Closed pair

(D) Open pair


10-The resultant unbalanced force is minimum in reciprocating engines when the part of the reciprocating mass balanced by rotating masses is

(A) 1/3

(B) 1/2

(C) 2/3

(D) 3/4


11-Hammer blow in locomotive results in

(A) Pulsating torque

(B) Tendency to lift the wheels from rail

(C) Uneven speed

(D) Variable horizontal force


12-The transfer function is the operational relationship of the output and the

(A) Command

(B) Response

(C) Input

(D) Error


13-If the ball masses of a governor have same equilibrium speed for all the radii of rotation, it is said to be

(A) Stable

(B) Hunting

(C) Isochronous

(D) Sensitive


14-In horizontal governor, if the stiffness of spring in increased, the governor will

(A) Become more sensitive

(B) Become less sensitive

(C) Remain affected

(D) Start hunting


15-A negative degree of freedom for a mechanism means

(A) Constrained motion mechanism

(B) Unconstrained motion mechanism

(C) Any motion

(D) Statically indeterminate structure


16-Oldham’s coupling and elliptical trammels are the inversion of

(A) Crossed slider crank chain

(B) Four bar chain

(C) Single slider crank chain

(D) Double slider crank chain



1-(C), 2-(B), 3-(A), 4-(D), 5-(D), 6-(D), 7-(C), 8-(A), 9-(B), 10-(B), 11-(B), 12-(C), 13-(C), 14-(B), 15-(D), 16-(D)