Electricity Flashcards
Power
The rate at which energy is transformed
Potential difference
The change in electric potential energy in two points in a circuit (Voltage)
Electric current
The movement of electrons
Electrical resistance
How difficult it is for current to travel through a material
Ohms law (equation)
the current in a circuit is equal to the potential difference divided by the resistance of the circuit ( I = V/R )
Kirchhoff’s rules
One for current, one for voltage
The total current in equals the total out
Equivalent resistance
Used to make a current more simple
Replaces multiple resistors with one
Series (ER)
Total equivalent resistance will always be bigger than any single resistor in the circuit
Parallel (ER)
The total resistance will always be smaller due to multiple paths which decrease the resistance and increase the current
Magnetic fields 🔁🧲
The distribution of a magnet force in the region of a magnet
Domain theory of magnets
All larger magnets are made up of smaller ones called dipoles, which interact with other dipoles close by.
If dipoles line up then a small magnetic domain is produced.
If a permanent magnet is broken, the pieces are also magnets, each with their own North and South
Orested’s discovery and principle ⚡
There is a link between electricity and magnetism
Charge moving through a conductor produces a magnetic field
Left handed rule #1
Straight conductor
-thumb is electron flow and fingers are magnetic field
Left handed rule #2
Solenoid
-fingers follow current and thumb is in the direction of North
Left handed rule #3
-fingers point to external magnetic field and South, thumb is in the direction of electron flow, force comes out of the palm
