What is ohms law?
Ohm’s Law explains the
relationship between voltage (V
or E), current (I) and resistance (R)
Used by electricians, automotive
technicians, stereo installers
Current refers to the
quantity/volume of electrical flow.
Measured in Amps (A)
It is the push or pressure behind
current flow through a circuit, and
is measured in (V) volts.
Resistance to the flow of the
current. Measured in Ohms
1. Assuming the resistance does not change:
As voltage increases, current increases.
As voltage decreases, current decreases.
2. Assuming the voltage does not change:
As resistance increases, current decreases.
As resistance decreases, current increases.
How do we used Ohms law
• V (E) = I x R
How do calculate?
Battery voltage is 12V
Current is Amp ?
Resistance 2 Ohm
How to calculate?
Voltage is 12V
Current is 4 Amps
Resistance Ohms ?
What can we use to measure?
Multi meters/ DVOM
Why do we need resistors
To decrease the amount of voltage
applied to a component
The value of the resistor is marked on the
body using coloured rings
Resistor color chart
What is a load
It is a any electric load on a circuit that
Example: Power windows, light
Different types of circuit
Series circuit :
One pathway for current to flow.
Example: Old Christmas lights
More then one path way for current to flow.
Used in most electrical vehicle circuits.
Series and Parallel Circuits
Parallel resistance circuit
What it looks like
1997 Headlight circuit
What is Voltage?
What is Current?
What is Resistance?
What are wiring diagrams?
What are the different circuits
and there characteristics?