Ohm's Law; Kirchhoff's Current Law - Cub Cadet 2000 Series Professional Shop Manual

Ohm's Law

Ohm's Law relates voltage, amperage, and resistance. It states that voltage is the product of resistance times
current.
I
Figure 7.40

Kirchhoff's current law

Kirchhoff's current law deals with nodes. Nodes are the junction of two or more wires or the junction of a wire to
a component.
Kirchhoff's current law states that what ever current goes into a node must come out.
Node
5 Amps
Figure 7.41
V
R
3 Amps
2 Amps
• It is written as V = I x R.
• In simplest terms, it goes like this:
• It takes 1 volt to push 1 amp through a resistance
of 1 ohm (1 = 1 x 1).
• This equation can be rearranged using algebra to
solve for any one variable.
• Those who were traumatized by algebra can rep-
resent Ohm's law as a triangle. When using the tri-
angle, cover the value to be found, and the two
values left exposed signify how to obtain that
value. See Figure 7.40.
• As an example if the "R" is covered, the "V" is over
the "I" which means "V" divided by "I" will solve for
the covered letter "R" (V/I = R).
• If the "V" is covered, "I" and "R" are exposed on the
same line, meaning that the product of "I" times "R"
will solve for the unknown "V" (I x R = V).
As an example: Three wires are connected with a wire
nut. One wire has 5 amps going into the connection:
• The sum of the currents coming out of the other
two wires must equal 5 amps. That could be 3
amps in one wire and 2 amps in the other or it
could be 2.5 amps in each wire, but the total com-
ing out must be the same as the current going in.
See Figure 7.41.
Electrical System
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