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and. The crank OA is running in the CCW direction. The mass of the connecting
rod AB is 4 kg and moment of inertia about its mass centre G is 0.052 kg-m and
mass of the slider is 2.5 kg. Assume that the crank OA is weightless. Determine the
magnitude and direction of the torque to be applied on the crank to balance the
inertia effects of the linkage

[er 150 mis”

OA= 15 ‏تت‎ AG=l5cm OA=
GB=30cm 15cm

88 = ॥ 20 m/s"

∎
AG=15cm
GB=30cm

PART B
Answer any threefull questions, each carries 10 marks.
A constant torque 2.5 kW motor drives a riveting machine. The mass of the moving
parts, including the flywheel is 125 kg at 70 cm radius. One riveting operation
absorbs 10,000] of energy and takes 1.2 seconds. Speed of the flywheel is 240 rpm
before riveting. Determine (1) No. rivets closed per hour and (2) the reduction in
speed after the riveting operation.

A shaft carries four rotating masses A of 5 kg, B of kg, C of 4.5 kg, and D of 3.5 kg
in this order from left to right. The effective radius of rotation of these masses from
the left are respectively 30 cm, 40 cm, 35 cm and 25 cm. The plane of rotation of A
and B are 35 cm apart and that between Band C are 45 cm apart. The angle between
the A and C is 120°.

Determine (i) the angle between A and B and that between A and D.
(ii) Distance between the planes of revolution of C and D,
(iii) the mass RIB, so that the system is incomplete
balance

The turbine rotor of a ship weighs 550 kN and has a radius of gyration of 0.45m
rotating at 2500 rpm in a CW direction when viewed from the aft. Ship pitches
t}uough a total angle of 12 °. Assuming that the motion is being simple harmonic
wiiil a period of 15 second, deterrnine (1) the maximum gyroscopic couple on the
holding down bolts of the turbine and using the vector diagram, find the direction
of yaw when the bow rises.

(10)

(10)

(10)