Marine Electrical 2008 Objective Paper

3. Which of the following statements best describes the material known as varnished cambric?

(A) Felted asbestos sealed with varnish.

(B) Cotton cloth coated with insulating varnish.

(C) Rubber insulation coated with a layer of tin.

(D) Paper impregnated with mineral oil, specially wrapped with nonmetallic tape, and coated with varnish. Briefly justify your answer


4. A synchronous motor maintains synchronism with the rotating field because _____________.

(A) field strength varies directly with rotors lIp

(B) DC current applied to the rotor coils causes the rotor magnets to lock in with the rotating flux of the stator

(C) the stator poles are dragged around due to the flux created by the excitation current

(D) the stator flux rotates in the opposite direction Briefly justify your answer


6. The part of a fuse that melts and opens the circuit is made of _____________.

(A) Copper and antimony

(B) Steel and Babbitt

(C) Aluminum or beryllium alloy

(D) Zinc or an alloy of tin and lead


Briefly justify your answer

1 the appereant powerin inductive circuit

a truepower

b lead

c inductive

d reactive


2 delayed action of fuse is meet ffrequency

a lightining

b motor

c radar

d none of above

3 the inductive loop of rotor simple two pole single phase generator rotates 400rps calculate frequency of induceed out put voltage N=120f/P

4 poly phase motor fails what cause for failure what should be check

a isolate motor

b remove fuse

c post cautions signs

d ensure starter motor terminals live


5 instrinsic semi conductor is dooped with small amount of boron in the extrinsic semi conductor formed the no of electron hole will precauton to take cleaning the motor with compressed air......... uscg refer

6 when reading electrical motor controller dealing its helps data logger for refregeration systems ... dnt know potions

8 break down diode____zener diode ___ and___avalanche diode____(reverse biasing)

9 basic measuring of inductance

a columb

b ohm

c faraday

d henry

10 open loop function system having one zero positiva real valueof __________ phase function

11 semmi conductor failed to over curent reason___low breakdown voltage___ and_________

12 sum 700w 36dayslike tht question 700xdays 36 x one day 24/ 1000

13 three resistor 40,50,60 connected in series input 30v calculate voltage drop across 60 resistor

Prepare for MMD Class 4 Objective