Ohm's Law Continued
So now we have 3 different ways that we can algebraically express Ohm's Law.
or
or
But of what significance is it? Here is the gist of it. If we know 2 out of
the 3 factors of the equation, we can figure out the third. Let's say we know
we have a 3 Volt battery. We also know we are going to put a 100
W
resistor in circuit with it. How much current can we expect will flow through
the circuit?
Without Ohm's Law, we would be at a loss. But because we have Ohm's Law, we
can calculate the unknown current, based upon the Voltage and Resistance.
Let's try another problem. Say we have the circuit below. We know the Voltage
and the Current, because we have meters to indicate such in the circuit. When
we plug in the unknown load resistance, the Voltmeter reads 45V and the Ammeter
reads 2 Amperes. What is the resistance of the load?
Well now, if'n I done my math a'right, I should be using this formula:
