Page 34 - Bebop to The Boolean Boogie An Unconventional Guide to Electronics Fundamentals, Components, and Processes

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Conductors and Insulators w 15

In a steady-state system Approx. actual size
where everything is constant, R

the voltage, current, and resis-
tance are related by a rule
(a) Discrete Component (b) Symbol
called Ohm’s Law, which states
that voltage (v) equals current Figure 3-3. Resistor:
(I) multiplied by resistance (R). component and symbol

An easy method for remembering
Ohm’s Law is by means of a diagram known as Ohm’s Triangle (Figure 3-4).

Figure 3-4. Ohm’s Triangle

Consider a simple electrical circuit com-
prising two wires with electrical potentials of
5 volts and 0 volts connected by a resistor of
10 ohms (Figure 3-5).9J0
This illustration shows the direction of
current flow as being from the more positive
(+5 volts) to the more negative (0 volts).
This may seem strange, as we know that
current actually consists of electrons migrat-
ing from a negative source to a positive target.

Ohm’s Law: V = IxR
9 Instead of writing “5 volts,” engineers would simply use I = VIR
“5V” (a useful rule to remember is that no space is used I = 5voltsll0ohms
for a single-letter qualifier like “5V,” but spaces are used I = 0.5amps
for multi-letter qualifiers like “5 Hz”).
10 The Greek letter omega “W is used to represent
resistance, so instead of writing “10 ohms,” engineers Figure 3-5. Current flowing
would typically use “IOQ.” through a resistor