University Institute of Engineering & Technology (UIET)
Babasaheb Bhimrao Ambedkar University, Lucknow-226025
Department of Mechanical & Automobile Engineering
Dynamics of Machines (EME-602)
Practice Questions
(Session-2023-24)
1.
Why is the inertia Governors quicker in action as compared to Centrifugal Governors? Explain
briefly.
2. What is meant by effort and power of a governor? Find the expression for the same in a porter
Governor.
3. Explain the terms sensitiveness, hunting and stability relating to governors?
4. A Porter governor has equal arms 200mm long pivoted on the axis of the rotations. The mass of
each ball is 3 kg and mass of the sleeve is 15 kg. The ball path is 120 mm when the governor
begins to lift and 160 mm at the maximum speed. Determine the range of the speed. If the
friction on the sleeve is equivalent of 10 N, find the coefficient of insensitiveness.
5. The Controlling force (Fc) in Newtons and the radius of rotation (r) in meters for a spring
controlled governor is given by the expression
Fc = 2800 r – 76
The mass of the ball is 5 kg and the extreme radii of rotation of the balls are 100 mm and 175
mm. Find the maximum and minimum speeds of the equilibrium. If the friction of the governor
mechanism is equivalent to a force 5 N at each ball, find the coefficient of insensitiveness of the
governor at the extreme radii.
6. Each ball of a porter governor has a mass of 3 kg and the mass of the sleeve is 15 kg. The
governor has equal arms each 200 mm long and pivoted on the axis of rotation. When the radius
of rotation of the balls is 120 mm, the sleeve begins to rise and 160 mm at the maximum speed.
Determine
(i)
the range of the speed
(ii)
the lift of the sleeve
(iii)
the effort of the Governor
(iv)
The power of the governor
7. The length of the ball and sleeve arms of the bell crank lever of a Hartnell governor is 140 and
120 mm respectively. The mass of the each governor ball is 5 kg. The fulcrum of the bell crank
lever is at a distance of 160 mm. At the mean speed of the governor which is 250 rpm, the balls
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are vertical and the sleeve arms are horizontal. The sleeve moves up by 12mm for an increase of
speed 4%. Neglecting friction, determine
(i)
The spring stiffness
(ii)
The minimum equilibrium speed when the sleeve moves by 24 mm
(iii)
The sensitiveness of the governor
(iv)
The spring stiffness for the governor to be isochronous at the mean speed
8. What is the condition of isochronous in governor? How are the controlling force curves drawn?
9. How do they indicate the stability or instability of a governor? Indicate the shape of such a curve
for an isochronous governor.
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