NM ES3: Questions With Well Organized Solutions
Wiring System Correct Ans - Is a form of electrical circuit.
Electrical circuit Correct Ans - Is comprised of an energy source, energy
transfer medium and a load.
Energy Transfer Medium Correct Ans - copper wire, fiber optic cables and
air in the case of radiated energy
Load Correct Ans - receives the transferred energy such as resistors,
lights, speakers, motors, etc.
EMF (electromotive force) Correct Ans - The force that moves electrical
energy.
Current or Current Flow Correct Ans - The movement of electrons
through a circuit that is caused by the electromotive force or voltage applied
to the circuit.
Inductance (L) Correct Ans - Unit is the henry. It is the property of a
circuit that causes an opposition to any change of current within the circuit. As
electrons flow, a magnetic field is produced. The magnetic force induces a
change in voltage.
Grounding Correct Ans - assures transmission of electrical signals without
interference from electromagnetic radiation from other transmission lines
and equipment. This interference, called crosstalk, can happen from adjacent
lines, motors, PCs, lights and other devices.
Grounding electrode Correct Ans - Connection to the electrode should be
less than 1 ft below the surface of the solid and the electrode should extend at
least 10 ft below ground.
Ground Loop Correct Ans - Causes a current to flow in the low resistance
of the shield resulting in electromagnetic waves that are picked up as noise
through the wire.
, 66 block Correct Ans - A punchdown block that terminates 22 to 26 AWG
solid copper wire. The 25 pair standard non split 66 block contains 50 rows.
110 block Correct Ans - To terminate on-premises wiring in structured
cabling. IDC or Insulation displacement contact connector is used to terminate
the twisted pair. The 110 allows for a much higher density of terminations,
less crosstalk and higher bandwidth data.
UF Correct Ans - Cable can be buried into the ground. Not approved for
commercial use in NM. 340.10
Balun Correct Ans - A means of matching an unbalanced antenna or
transmission line to a balanced transmission line or antenna (Usually have a
transformer in them)
Bus Topology Correct Ans - All nodes are connected to a single shared
communication line
Ring Topology Correct Ans - Topology where the computers are
connected on a loop or ring.
Star Topology Correct Ans - A topology with one central node that has
each computer or network device attached to the central node. All data first
goes into the central node and then is sent out to its destination.
Transducer Correct Ans - A device that converts energy from one form to
another
Crossover Correct Ans - Divide an output into separate circuits each
covering a specific band or frequency range.
inverse square law Correct Ans - Each doubling of distance from the
sound source results in a fourfold reduction of sound power (equal to 6db). If
one moves 4' to 8' from a sound source, the level is reduced by 6 db. Double
the distance to 16' and the level is reduced another 6db to 12 db.
Dry Contact Devices Correct Ans - Normally open switch which close on
activation and creates and alarm. Pull stations, heat detectors, four wire
smoke detectors, sprinkler supervisory switches.
Wiring System Correct Ans - Is a form of electrical circuit.
Electrical circuit Correct Ans - Is comprised of an energy source, energy
transfer medium and a load.
Energy Transfer Medium Correct Ans - copper wire, fiber optic cables and
air in the case of radiated energy
Load Correct Ans - receives the transferred energy such as resistors,
lights, speakers, motors, etc.
EMF (electromotive force) Correct Ans - The force that moves electrical
energy.
Current or Current Flow Correct Ans - The movement of electrons
through a circuit that is caused by the electromotive force or voltage applied
to the circuit.
Inductance (L) Correct Ans - Unit is the henry. It is the property of a
circuit that causes an opposition to any change of current within the circuit. As
electrons flow, a magnetic field is produced. The magnetic force induces a
change in voltage.
Grounding Correct Ans - assures transmission of electrical signals without
interference from electromagnetic radiation from other transmission lines
and equipment. This interference, called crosstalk, can happen from adjacent
lines, motors, PCs, lights and other devices.
Grounding electrode Correct Ans - Connection to the electrode should be
less than 1 ft below the surface of the solid and the electrode should extend at
least 10 ft below ground.
Ground Loop Correct Ans - Causes a current to flow in the low resistance
of the shield resulting in electromagnetic waves that are picked up as noise
through the wire.
, 66 block Correct Ans - A punchdown block that terminates 22 to 26 AWG
solid copper wire. The 25 pair standard non split 66 block contains 50 rows.
110 block Correct Ans - To terminate on-premises wiring in structured
cabling. IDC or Insulation displacement contact connector is used to terminate
the twisted pair. The 110 allows for a much higher density of terminations,
less crosstalk and higher bandwidth data.
UF Correct Ans - Cable can be buried into the ground. Not approved for
commercial use in NM. 340.10
Balun Correct Ans - A means of matching an unbalanced antenna or
transmission line to a balanced transmission line or antenna (Usually have a
transformer in them)
Bus Topology Correct Ans - All nodes are connected to a single shared
communication line
Ring Topology Correct Ans - Topology where the computers are
connected on a loop or ring.
Star Topology Correct Ans - A topology with one central node that has
each computer or network device attached to the central node. All data first
goes into the central node and then is sent out to its destination.
Transducer Correct Ans - A device that converts energy from one form to
another
Crossover Correct Ans - Divide an output into separate circuits each
covering a specific band or frequency range.
inverse square law Correct Ans - Each doubling of distance from the
sound source results in a fourfold reduction of sound power (equal to 6db). If
one moves 4' to 8' from a sound source, the level is reduced by 6 db. Double
the distance to 16' and the level is reduced another 6db to 12 db.
Dry Contact Devices Correct Ans - Normally open switch which close on
activation and creates and alarm. Pull stations, heat detectors, four wire
smoke detectors, sprinkler supervisory switches.
