Explore topic-wise MCQs in Machine Dynamics.

This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Machine Dynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

A ship propelled by a turbine rotor which has a mass of 5 tonnes and a speed of 2100 r.p.m. The rotor has a radius of gyration of 0.5 m and rotates in a clockwise direction when viewed from the stern. Find the gyroscopic effect when the ship sails at a speed of 30 km/h and steers to the left in a curve having 60 m radius.

A. 38.5 kN-m
B. 48.5 kN-m
C. 58.5 kN-m
D. 68.5 kN-m
Answer» B. 48.5 kN-m
Discussion
2.

The mass of the turbine rotor of a ship is 20 tonnes and has a radius of gyration of 0.60 m. Its speed is 2000 r.p.m. The ship pitches 6 above and 6 below the horizontal position. A complete oscillation takes 30 seconds and the motion is simple harmonic. Determine Maximum angular acceleration of the ship during pitching.

A. 0.0016 rad/s<sup>2</sup>
B. 0.0026 rad/s<sup>2</sup>
C. 0.0036 rad/s<sup>2</sup>
D. 0.0046 rad/s<sup>2</sup>
Answer» E.
Discussion
3.

The mass of the turbine rotor of a ship is 20 tonnes and has a radius of gyration of 0.60 m. Its speed is 2000 r.p.m. The ship pitches 6 above and 6 below the horizontal position. A complete oscillation takes 30 seconds and the motion is simple harmonic. Determine Maximum gyroscopic couple.

A. 11.185 kN-m
B. 22.185 kN-m
C. 33.185 kN-m
D. 44.185 kN-m
Answer» D. 44.185 kN-m
Discussion
4.

The turbine rotor of a ship has a mass of 3500 kg. It has a radius of gyration of 0.45 m and a speed of 3000 r.p.m. clockwise when looking from stern. Determine the gyroscopic couple upon the ship when the ship is pitching in a simple harmonic motion, the bow falling with its maximum velocity. The period of pitching is 40 seconds and the total angular displacement between the two extreme positions of pitching is 12 degrees.

A. 3.675 kN-m
B. 4.675 kN-m
C. 5.675 kN-m
D. 6.675 kN-m
Answer» B. 4.675 kN-m
Discussion
5.

The turbine rotor of a ship has a mass of 3500 kg. It has a radius of gyration of 0.45 m and a speed of 3000 r.p.m. clockwise when looking from stern. Determine the gyroscopic couple upon the ship when the ship is steering to the left on a curve of 100 m radius at a speed of 36 km/h.

A. 11.27 kN-m
B. 22.27 kN-m
C. 33.27 kN-m
D. 44.27 kN-m
Answer» C. 33.27 kN-m
Discussion
6.

The heavy turbine rotor of a sea vessel rotates at 1500 r.p.m. clockwise looking from the stern, its mass being 750 kg. The vessel pitches with an angular velocity of 1 rad/s. Determine the gyroscopic couple transmitted to the hull when bow is rising, if the radius of gyration for the rotor is 250 mm.

A. 4.364 kN-m
B. 5.364 kN-m
C. 6.364 kN-m
D. 7.364 kN-m
Answer» E.
Discussion
7.

The turbine rotor of a ship has a mass of 8 tonnes and a radius of gyration 0.6 m. It rotates at 1800 r.p.m. clockwise, when looking from the stern. Determine the gyroscopic couple, if the ship travels at 100 km/hr and steer to the left in a curve of 75 m radius.

A. 100.866 kN-m
B. 200.866 kN-m
C. 300.866 kN-m
D. 400.866 kN-m
Answer» C. 300.866 kN-m
Discussion
8.

An aeroplane makes a complete half circle of 50 metres radius, towards left, when flying at 200 km per hr. The rotary engine and the propeller of the plane has a mass of 400 kg and a radius of gyration of 0.3 m. The engine rotates at 2400 r.p.m. clockwise when viewed from the rear. Find the gyroscopic couple on the aircraft.

A. 10.046 kN-m
B. 11.046 kN-m
C. 12.046 kN-m
D. 13.046 kN-m
Answer» B. 11.046 kN-m
Discussion
9.

A uniform disc of diameter 300 mm and of mass 5 kg is mounted on one end of an arm of length 600 mm. The other end of the arm is free to rotate in a universal bearing. If the disc rotates about the arm with a speed of 300 r.p.m. clockwise, looking from the front, with what speed will it precess about the vertical axis?

A. 14.7 rad/s
B. 15.7 rad/s
C. 16.7 rad/s
D. 17.7 rad/s
Answer» D. 17.7 rad/s
Discussion