Machine Dynamics

Hartnell Governor

Question 1
Marks : +2 | -2
Pass Ratio : 100%
In a spring controlled governor, when the controlling force _____________ as the radius of rotation increases, it is said to be a stable governor.
remains constant
decreases
increases
none of the mentioned
Explanation:
For the governor to be stable, in spring controlled governor, the controlling force must increase as the radius of rotation increases.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
The power of a Porter governor is equal to
c2/1 + 2c (m + M)gh
2c2/1 + 2c (m + M)gh
3c2/1 + 2c (m + M)gh
4c2/1 + 2c (m + M)gh
Explanation:
The effort of a Porter governor is equal to c(m + M)g.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
The effort of a Porter governor is equal to
c(m – M)g
c(m + M)g
C/(m + M)g
Explanation:
The effort of a Porter governor is equal to c(m + M)g.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
A spring controlled governor is said to be stable if the controlling force line when produced intersects the Y-axis
at the origin
below the origin
above the origin
any of the mentioned
Explanation:
A spring controlled governor is said to be stable if the controlling force line when produced intersects the Y-axis below the origin.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
Power of a governor is the
mean force exerted at the sleeve for a given percentage change of speed
workdone at the sleeve for maximum equilibrium speed
mean force exerted at the sleeve for maximum equilibrium speed
none of the mentioned
Explanation:
The power of a governor is the work done at the sleeve for a given percentage change of speed. It is the product of the mean value of the effort and the distance through which the sleeve moves. Mathematically,
Question 6
Marks : +2 | -2
Pass Ratio : 100%
The controlling force diagram for a spring controlled governor is a curve passing through the origin.
True
False
Explanation:
The controlling force diagram for the spring controlled governors is a straight line.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
A spring controlled governor is found unstable. It can be made stable by
increasing the spring stiffness
decreasing the spring stiffness
increasing the ball mass
decreasing the ball mass
Explanation:
For the governor to be stable, in spring controlled governor, the controlling force must increase as the radius of rotation increases.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
A spring controlled governor is said to be unstable when the controlling force
increases as the radius of rotation decreases
increases as the radius of rotation increases
decreases as the radius of rotation decreases
remains constant for all radii of rotation
Explanation:
If the equilibrium speed of the governor decreases with an increase of the radius of rotation of balls, then the governor is said to be unstable.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
For the isochronous Porter governor, the controlling force curve is a straight line passing through the origin.
True
False
Explanation:
For the isochronous governor, the controlling force curve is a straight line passing through the origin. The angle φ will be constant for all values of the radius of rotation of the governor.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
A spring controlled governor is said to be isochronous when the controlling force
increases as the radius of rotation decreases
increases as the radius of rotation increases
decreases as the radius of rotation decreases
remains constant for all radii of rotation
Explanation:
For the governor to be stable, in spring controlled governor, the controlling force must increase as the radius of rotation increases.