# Gyroscopic Effect MCQ and Gyroscopic Couple MCQ

1. The effect of gyroscopic couple on roling of ships is

1. very low
2. very high
3. moderate
4. no effect

2. Consider the following statements:

1. Gyroscopic effects generate forces and couples which act on the vehicles, and these effects must be taken into account while designing their bearings.
2. Rolling motion of a ship usually occurs because of the difference in buoyancy on the two sides of the ship due to a wave.

Which of the above statements is/are correct?

1. i only
2. ii only
3. Both i and ii
4. Neither i nor ii

3. If the air screw of an aeroplane rotates clockwise when viewed from the rear and the aeroplane takes a right turn, the gyroscopic effect will

1. tend to raise the tail and depress the nose
2. tend to raise the nose and depress the tail
3. tilt the aero lane about spin axis
4. none of above

4. The propeller of an aeroplane is rotating in the clockwise direction when viewed from the rear end. If the plane takes left turn, then the gyroscopic effect cause the

1. nose of the plane to depress and tail of the plane to raise
2. nose of the plane to raise and tail of the plane to depress
3. no effect on the nose and tail of the plane
4. plane to take right turn
5. speed of the plane will be doubled

5. When the pitching motion causes the bow to rise, the rotor rotating in clockwise sense (as seen from stern) the gyroscopic effect tends to

1. turn the ship towards port side
2. turn the ship towards star-board side
3. depress the stern
4. raise the stern

6. The gyroscopic acceleration depends upon

1. instantaneous value of axis ω
2. the rate at which the axis of spin changes its speed
3. both a and b
4. none of these

7. The active gyroscopic torque in gyroscope about a horizontal axis represents

1. the torque required to cause the axis of spin to process in the vertical plane
2. the torque required to cause the axis of spin to process in the horizontal plane
3. the force required to cause the axis of spin to process in the horizontal plane
4. the force required to cause the axis of spin to process in the vertical plane

8. If the axes of the rolling of the ship and of the stabilizing rotor are parallel, it will result in

1. a higher bow and lower stern
2. a lower bow and higher stern
3. turning towards left
4. no gyroscopic effect

9. The axis of spin, the axis of precession and the axis of gyroscopic torque are in

1. Two parallel planes
2. Two perpendicular planes
3. Three perpendicular planes
4. Three parallel planes

10. An aircraft cruising at 360 kmph takes a right turn on an arc of 100 m radius. The turbines and propellers have a total mass of 500 kg with radius of gyration of 25 cm. The engine rotates at 2000 r.p.m. The magnitude of the gyroscopic couple generated is

1. 6.55 kN m
2. 7.65 kN m
3. 13.1 kN m
4. 9.81 kN m

11. The rotor of ship rotates in clockwise direction when viewed from the stern and the ship takes a left turn. The effect of the gyroscopic couple acting on it will be

1. to raise the bow and stern
2. to lower the bow and stern
3. to raise the bow and lower the stern
4. to raise the stern and lower the bow

12. The engine of aeroplane rotates in clockwise direction when seen from the tail end and the aeroplane takes a turn to the left. The effect of the gyroscopic couple on the aeroplane will be

1. to dip the nose and raise the tail
2. to raise the nose and tail
3. to dip the nose and tail
4. to raise the nose and dip the tail

13. An aeroplane moving with a velocity of 300 Kmph negotiates a turn along a circular path of radius 600 m. If the angular velocity of the rotating parts of the plane is 120 rad/s and the moment of inertia of the rotating parts is 60 kg.m2, the gyroscopic couple is

1. 500 Nm
2. 1000 Nm
3. 3000 Nm
4. 5000 Nm

14. The rotor of a ship with moment of inertia 200 kgm2 and rotational speed of 200 rad/s. What will be the gyroscopic couple when ship turns to left at radius of 100 m with speed 5 m/s?

1. 20 Nm
2. 2000 Nm
3. 200 Nm
4. 2 Nm