D:-All of the above
Correct Answer:- Option-D

Question78:-The instrument used for measuring heading angle and which does not depend on Earth's magnetic field is
called

A:-Gyrocompass
B:-Magnetic compass
C:-Tachometer
D:-Speedometer

Correct Answer:- Option-A

Question79:-The yaw motion equation for 6 DoF motion is expressed as follows. The terms ‘I_{zx}, |_{zy}, |_{xy}* are part
of:

` | {टर} 6௦041 (20) (0010-10) * |_{zy} (dotq + rp) +1_{xy} (02:92) *
(൧ - L{text {xx}}) pq+ mx_G (dotv+ur-wp) = N*

A:-Inertia tensor

B:-Inertia matrix

C:-Mass matrix

D:-(1) and (2)

Correct Answer:- Option-D
Question80:-The 3 DoF motion equation of surface ship is given below :

*m [dotu-vr-x_{G} r*2] = -A_{11} dotu +X_{text{uu}} u*2 +a_3v*2 +a_7 r*2 +a_9 vr+X_P+X_R°

*m [dotv +ur-x_G dotr] =*

*-A_{22} doty - A_{26} dotr -A_{11}urt+b_lv+b_3r+b_{13}v*2r+b_{15} vr*2 + b_{26} v*3 ‏3ہ(28) _ج+‎ +۷۵ +۷8۰
| (22) dotr =

*-A_{62} dotv - A_{66} dotr - (A_{22}-A_{11}) uv-A {26} ५1 + 1५ + {3 1 + 1 {13} ५^2 1 {15} ५^2 + { {26} ५^३
+ {28} 1^3 + ॥?+॥ रि

Itisa differential equation.
A:-Coupled and linear
B:-Partial
C:-Coupled and non linear
D:-None of the above
Correct Answer:- Option-C

Question81:-The sway + yaw coupled oscillation motion equation and PD autopilot equation at steady forward speed for a
ship is given below. When expressed in the state space form ‘Adotx=Bx+Cz° , the size of A matrix will be:

“[L(m'-¥'"_{dotv}), YL[-(N'_{dotv}-m'x'_{CG}), (I'_Z-N'_{dotr})]] *((dotv'),(dotr'))” = “[[(Y'_v), Y'LL(N'_v), mT} ((v'),(r))° +
*((Y'_{delta} delta_R),(N'_{delta} delta_R))*

‘T'_E dotdelta' = K'_P (psi_d - psi) - T'_D(r') - delta_R*
A: 4 xx 4
B:-No
C:-Sway
D:-(1) and (2)
Correct Answer:- Option-A
Question82:-Explain why a conventional merchant ship heels when the rudder angle is given. Does the direction of heel
angle change as the ship's sway + yaw dynamics build up?
A:-Roll moment is induced because rudder is offset from ship's vertical centre of gravity. Yes
B:-Pitch moment is induced because rudder is offset from ship's vertical centre of gravity. No
C:-Incorrect statement
D:-(1) and (2)
Correct Answer:- Option-A
Question83:-For a moving ship rudder is more effective at the of a ship.
A:-Forward
B:-Pitch
C:-Aft
D:-(1) and (2)
Correct Answer:- Option-C