Module Revision

1

main source of electrical power

A

a part of an atom with no charge (electrically neutral).

2

emergency source of electrical power

B

an apparatus for reducing or increasing the voltage of an alternating current

3

conductor

C

relatively small electromotive force or potential difference expressed in volts

4

electricity

D

a material or device that conducts or transmits heat or electricity, especially when regarded in terms of its capacity to do this

5

high voltage

E

a source intended to supply electrical power to the main switchboard for distribution to all services necessary for maintaining the slip in normal operational and habitable conditions.

6

low voltage

F

an electrical potential large enough to cause injury or damage

7

transformer

G

energy made up of moving electrons

8

nucleus

H

a source of electrical power, intended to supply the emergency switchboard in the event of failure of the supply from the main source of electrical power.

9

neutron

I

the force inside the atom that is responsible for electrical phenomena, existing in a positive or negative form.

10

charge

J

the positively charged center of an atom.

1. Electrical power is used ____ the majority of these auxiliary services.

a)to measure

b) to drive

c)to flow

2.The main AC generators (sometimes called ______) produce the electrical power.

a) wires

b) batteries

c) alternators

3. The power is supplied to the main ____ and then distributed to the various auxiliary services

a)generator

b)gearbox

c) switchboard

4. An emergency generator maintains supplies in the event of a main power____.

a) failure

b)circuit

c)run

5. The generators may be driven by the main propulsion engine as a ______ generator.

a)AC

b)shaft

c)DC

6.Electrical power on board ship is commonly generated at ________.

a) 220 V, 50 Hz

b) 320 V, 40 Hz

c) 440 V, 60 Hz

7. Ships with a very large electrical power demand will require ____ that operate at a high voltage.

a) generators

b)batteries

c)propulsion engine

8. ______ are used to reduce the 440 V system voltage to these lower voltage levels.

a)generators

b) transformers

c)switchboards