1. Electric Resistance
describes how an electrical conductor (wire) opposes the flow of a current (flow of electrons)
to overcome this opposition a voltage (energy) most drop (used) across the conductor (wire)
resistance can be described by Ohms Law:
𝑅= 𝑉 𝐼
R – resistance – measured in Ohms (𝞨)
V – voltage – energy lost across a component (volts – V)
I – current charge (electrons) flowing through a component
– measured in amps (A)
Electric Resistance Simulator
Battery – Resistor Circuit

2. Electrical resistance can be thought of as sticking your hand out a car window
The faster (current) you drive the harder the wind presses (resistance) against your hand
Therefore, it takes more energy (voltage) to hold your hand steady
Examples
common resistor
stove element
toaster
light bulb

3. Example
The voltage across a light bulb is 120 V and the current flowing through the bulb is 0.833A. Calculate the resistance of the light bulb.
V = 120 V
I = 0.833A
R = ?
R = 𝑉 𝐼 =
= 144
\ the resistance is 144 Ω