Honolulu star-bulletin. [volume] (Honolulu [Oahu, Hawaii]) 1912-2010, 1916-09-16

neither beginning nor end. II we start
at any point on the electrical circuit
and follow along the circuit we win
arrive e the point from which we
'Ef1ffei inst shzs we return % the xiatE
Ing paint y following along a circle,
REGARDLESS q ihe point from which .el
we Atafteu q
il order to einphasize the import.
ance 81 the reader getting this circuit
or circle idea thoroughly insmihd, the
various circuits Of the modern motor
car ere indicated IN the circular form
IN one of the accompanying iIlustra-
tions.
i These circuits aud their relations to
each other will be taken up in detail
later. II Is not humanity possible TO
make changes or locate troubles in the
electrical equipment Of car unless
this circuit idea is followed, either
consciously or nnconsciously.
The circle or circuit is to electricity
what the metal rails are to the rail-
road train. Your train cannot run
without the track. as electricity cam
not be made use Of except in cir
cult.
Electrical Current
Il is obvious that the action Of the
pump IN the water circuit and the &C.
tion of the battery in the electrical
circuit are very similar. There is Q
mechanical pressure produced by the
pump which causes the water to now
through the pipe. and the battery pro-
duces what Is called an electrical pres
sure which causes the electricity to
flow through the wire.
II the mechanical pressure produced
by the pump be increased or decreased
there VIII be q change In the flow OF
the water In the pipe. the flow In.
Icreasing with an increase In pressure
and decreasing with q decrease in
pressure. This flow, or movement OF
the water in the pipe, may be meas
ured by determining the number OF
gallons passing q certain point in the
pipe IN. say, one second. You could
then speak Of the flow Of water In the
pipe as being SO many gallons sec
ond. any unit of quantity and time
may be used III expressing the flow OF
water in q pipe, such as so many cubic
feet minute, so many gallons an
hour, etc.
The flow or movement of electricity
I'm the electrical circuit is measured
In Q similar manner to the flow OF
water In q pipe; that is, by determin.
ing the quantity OF electricity passing
certain point in the electrical cir
cult In certain time Instead OF
measuring the quantity Of electricity
in gallons or cubic feet. as in the
measurement OF water. it is measured
in unit called the coulomb.
In referring to certain quantity OF
electricity 1t is spoken OF as so many
eoulombs, Just as certain quantity
OF water is spoken OF as so many gal
Ions. so many cubic feet, etc.
The Ampere
II the water in a pipe is moving at
such a rate that there is one gallon
OF water passing every point along
the pipe each second there Is said to
be flow of one gallon second In the
pipe. Similarly, II the electricity in q
circuit is moving at such q rate that
] there Is one coulomb passing every
point in the circuit In each second of
time there is said to be q flow Of
one coulomb second. The flow, or
movement Of the water in the pipe, is.
called the current of water, just as
the flow Of the water in a river is
called the current and, likewise. the
flow of the electricity in the electrical
circuit Is called the current Of cleo
tricity, or. more commonly. the cleo
trical circuit. From the foregoing it
is seen that the current Of water is
EXPRESSED as so many gallons sec
ond so many cubic feet minute, etc.
while the current Of electricity as so