Specifications

183
Resistance Formula Calculations
How to read the Ohm's Law wheel
Resistance = Voltage / Current
Resistance = Voltage
2
/ Power
Resistance = Power / Current
2
Example:
If you know a circuit has a voltage potential of 12
Volts and 6 Amps of current is passing through
it, then you can calculate the resistance in that
circuit: 12 ÷ 6 = 2. The circuit has a resistance of
2 Ohms.
Voltage Formula Calculations
Example 1:
If you know a device (a resistor for example) has
2A of current being passed through it and has
a resistance of 10 Ohms, then the voltage drop
across the resistor will be: 2 x 10 = 20V
Example 2:
If you know a device is dissipate 10 Watts of
power and has a resistance of 20 Ohms, then
you can calculate the voltage being applied to the
device: (10 x 20) = 14.14 Volts.
Current Formula Calculations
Example 1:
If you know a device is dissipating 100W of
energy and has a resistance of 4 Ohms, you can
calculate the current being passed through the
device: (100 ÷ 4) = 5 Amps
Power Formula Calculations
Example 1:
If you know a device is dissipating 100W of power
and 12V is being applied to the device, you can
calculate the current passing through the device:
100 ÷ 12 = 8.33A
Car Audio Reference Guide