# MCQs on Mechanical Actuating Systems – KInematic Chains

1 - Question

Which Equation can be used to determine the “degree of freedom” of a system?
a) Gruebler’s equation
b) Fourier Transform
c) Simon’s equation
d) Maxwell’s equation
Explanation: Gruebler’s equation can be used to determine the “degree of freedom” of a system. This equation is used to determine the degree of freedom of planar linkages that are joined with a common joint.

2 - Question

Which combination of pairs forms compound joints?
a) Higher pair-Higher pair combination
b) Higher pair-Lower pair combination
c) Lower pair-Lower pair combination
d) Universal pair-Lower pair combination
Explanation: A compound joint is a combination of higher pair and lower pair. These pairs are combined according to the requirement of the design. The arrangement of these combinations can be altered to obtain robust joints.

3 - Question

Which kinematics is used to calculate the joint parameter which will be used to place at the end of the kinematic chain?
a) Forward Kinematics
b) Reverse Kinematics
c) Inverse Kinematics
d) Backward Kinematics
Explanation: Inverse kinematics is used to calculate the joint parameter which will be used to place at the end of the kinematic chain. It is a mathematical process that is generally used in animating the skeleton of a character. advertisement

4 - Question

Which kinematics is used to calculate the position of end-effector from some specified values?
a) Forward Kinematics
b) Reverse Kinematics
c) Inverse Kinematics
d) Backward Kinematics
Explanation: Forward kinematics is used to calculate the position of end-effector from some specified values. It is a kinematic equation, generally used in robots for the gripping purpose of any object.

5 - Question

Gruebler’s equation can be used to determine degree of freedom of non planar linkages.
a) True
b) False
Explanation: Gruebler’s equation cannot be used to determine degree of freedom of non planar linkages. It can be used to determine the degree of freedom of planar linkages that are joined with a common joint.

6 - Question

Cam joint is a lower pair.
a) True
b) False
Explanation: Cam joint is not a lower pair. It is an example of higher pair. In these types of pairs the contact between the members has a line or point geometry. These pairs experience high stress at the point of contact due to very less area of contact.

7 - Question

Hinge joint is an example of higher pair.
a) True
b) False
Explanation: Hinge joint is not an example of higher pair. It is an example of lower pair. The members of lower pairs have common mating surface. Hinge joint has a considerable amount of contact area, so it is an example of lower pair.

8 - Question

What does degree of freedom in a kinematic chain denotes?
a) Total parameters of kinematic chain
b) Length of kinematic chain
c) Joints in kinematic chain
d) Type of kinematic chain
Explanation: The degree of freedom represents parameters that are used to define the configuration of a kinematic chain. It also represents the mobility or the total possible movements of a kinematic chain.

9 - Question

What is the joint called if only four links are joined at a point?
a) Binary joint
b) Ternary joint
c) Quaternary joint
Explanation: When only four links are joined at a point then the joint is known as Quaternary joint. When only three links are joined at a point then the joint is known as Ternary joint. When only two links are joined at a point then the joint is known as Binary joint. Bi-joint does not exist.

10 - Question

Who is termed as the father of kinematics?
a) Nick brown
b) Franz Reuleaux
c) Stefencolumbus
d) Billy Stern
Explanation: Franz Reuleaux is termed as the father of kinematics. He was German mechanical engineer and a lecturer at the Berlin Royal Technical Academy born on September 30, 1829. He was later declared as the president of the academy.

11 - Question

What is the joint called if only three links are joined at a point?
a) Binary joint
b) Ternary joint
c) Quaternary
d) Tri-joint
Explanation: When only three links are joined at a point then the joint is known as Ternary joint. When only two links are joined at a point then the joint is known as Binary joint. When only four links are joined at a point then the joint is known as Quaternary joint. Tri-joint does not exist.

12 - Question

Members of lower pairs have line geometry.
a) True
b) False
Explanation: Members of lower pairs do not have line geometry. They have plane geometry. They have a large area of contact; therefore the stress at the area of contact is less. Members of higher pairs have line or point geometry.

13 - Question

Lower pairs are the pairs that are joined together with surface contact between them.
a) True
b) False
Explanation: Lower pairs are the pairs that are joined together with surface contact between them. There are two types of pair’s lower pairs and higher pairs. The members of higher pairs have a line or point geometry.

14 - Question

Which equation represents Grubler’s equation? (where “F”represents Degrees of freedom, n represents number of links, l represents Number of lower pairs, h represents Number of higher pairs)
a) F = 3(n-1)-2l-h
b) F = 2(n-1)-2l-h
c) F = 2(n-1)-3l-h
d) F = 3(n-1)-2l-2h
Explanation: F = 3(n-1)-2l-h represents Grubler’s equation. (where “F”represents Degrees of freedom, n represents number of links, l represents Number of lower pairs, h represents Number of higher pairs). This equation is used to determine the Degree of freedom of a system.

15 - Question

What is the joint called if only two links are joined at a point?
a) Binary joint
b) Ternary joint
c) Quaternary joint
d) Bi-joint