What is the law of Magnetism?
like poles repel, opposite poles attract
what is static electricity?
An imbalance of charges where an object becomes positively or negatively charged.
do conductors or insulator get charged with static electricity?
Only insulators. they gain or lose electrons.
What are electric field
A region in which a charged object will experience an electric force
Resistance
measure of how difficult it is for charge to flow through a circuit
Current
Flow of electrons around a circuit
Potential difference
The energy given to each Columbus of charge around 2 points in a circuit
In a series circuit, the current…
The current is the same everywhere.
In a series circuit, the p.d. Is…
Split amongst the component
In a parallel circuit, the current is…
Shared. As it split up in each branch according to the component. And the total current going into a conjunction = the total current leaving.
In a parallel circuit, the p.d. Is..
the p.d. is the same on every branch
( meaning that eac branch gets full battery voltage)
Adding a resistor in a series circuit…
Decreases the total current, and increases the total resistance
Adding a resistor in a parallel circuit…
Increases the total current and decreases the total resistance
Voltmeter
Measure the pd, it should always be placed in parallel to a circuit
Ammeter
Measures the current. Should always be placed in series to the circuit.
Ammeter
Measures the current. Should always be placed in series to the circuit.
formula that links PD and current
V= IR
How does the length of a wire affect its resistance?
The longer the wire, the greater its resistance due to increased collisions between electrons and atoms in the wire.
Lamps’s Graph
Curve graph. As the voltage increases, the filament heats up. and the heat causes the resistance to increase. So the current increases slowly
Ohmic conductors
Straight line. Pd and current are directly proportional.
Graph of Diodes
Flat to steep quick. Resistance depends on the direction of the current. They let current flow in one direction, but has a very high resistance if the current is reversed.
Variable resistor
A resistor that can change its resistance
LDR (light dependant resistor)
As the light intensity increase, the resistance decreases.
(Used in street lights)
Thermistor
The higher the temperature, the lower the resistance.
(Used in car engines)
