Energy

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Electricity and Magnetism

They are both intertwined because they are bot caused by the interaction of positive and negative matter. When charges in matter interact, they can produce both electric and magnetic forces.

ELECTRIC CHARGE AND FORCE:

All atoms are made out of electrons and protons.

When the number of electrons and protons are equal in an atom they cancel each other out and the charge becomes neutral.

Atoms gain and lose electrons easily

When an atom gains electrons, it has a negative charge

When an atom loses electrons, it had a positive charge

Positively or negatively charged atoms are called ions

Like charges repel and unlike charges attracts

ions create attractive and repulsive forces called electric forces

STATIC ELECTRICITY/CHARGE

When an electric charge builds up on an object and transfers from one body to another.

like rubbing a balloon on your hair, can create static charges.

ELECTRIC/STATIC DISCHARGE

Opposite of static electricity

like lighting which is an enormous electric discharge

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ELECTRIC FIELDS

The area around an electric charge that experiences the force exerted by the electric charge.

farther you are from the charge the weaker field is and the closer you are to the charge the stronger the field

electric field lines show the direction of the electric force ( points towards negative charge and away from positive charge)

INDUCTION

The separation of charges caused by an electric field.

Example: when you put a balloon that is negatively charged close to a wall, the balloon will repel other electrons pushing them away from that area and create a localized temporary positive charge. You can get a balloon to stick to the wall because of this.

Insulators: material that doesn't allow electrons to move easily. Examples: glass, plastic, rubber, porcelain, styrofoam.

Conductors: material that lets electrons move easily through it. Examples: metal, gold, copper.

Resistor: something that resists the flow of electrons. Examples: thin wire (filament) in a lightbulb.

ELECTRIC CURRENT

The number of electrons that pass a given point in a certain amount of time

When electric charges move they create an electric current. It's measured in amperes (A) or amp.

Types of currents:

Direct current (DC): electric charges in current move in one direction, like in a battery

Alternative current (AC): the flow of electrical charges that alternate direction from time to time, like the electricity from an outlet

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ELECTRICAL CIRCUIT

An electric current will flow continuously if the charges can travel in a closed conducting loop. The electric field kees the charged moving.

Components of a circuit

Electrical conductor: Like a wire, which connects to the power source forms a closed-loop ( a connection with no openings or breaks).

Load: a device that the circuit is powering, like a lightbulb, fan, speaker etc. The load isn't necessary but there most of the time.

Power source: of electrical energy such as a battery.

Switch: Device to open and close a circuit. The switch isn't necessary but mostly there.

Series circuit: When there is only one way an electron can travel through a circuit. All current flows in one direction, through every element of the circuit. If the circuit is open at any point the electrical flow will stop in the entire circuit.

Parallel circuit: The electrons can take more than one path. When the path is broken the current can flow because there are alternate paths for the current to follow.

BATTERIES

Is the energy source a circuit, it pushes the electric charges around. When connected to a circuit the battery creates an electrical field with positive and negative terminals. The electrons are attracted to the positive and repelled by the negative.

VOLTAGE

The amount of potential energy an electron in a circuit can gain. It's measured in volts.

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Resistance

How hard it is for electrons to travel through something, As electrons move in a current, they can bump into things which makes it harder to travel. It's measured in ohms.

wires with less resistance are more efficient

resistance in a wire increases as the wire gets thinner/longer

energy in high resistance wires can be lost in the form of thermal energy through collisions

the lightbulb in a circuit provides resistance.

OHMS LAW

voltage = current x resistance

volts amperes ohms

when resistance decreases current increases

when resistance increases current decreases

ELECTRIC POWER

Power the rate at which electrical energy is transformed into other forms of energy.

Power = current x voltage

watts amperes volts

CONSERVATION OF ENERGY IN CIRCUITS

Electrical energy also follows the law of conservation energy. As the current travels through a circuit, electrical energy is converted into thermal energy, light or kinetic energy.

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MAGNETIC FORCE

Is an attractive and repulsive force between opposite poles.

Pole: strongly charged of a magnet

MAGNETIC FIELDS

The area around a magnet that experiences a magnetic force

Magnetic field lines: show the direction and strength of the magnetic field. Magnetic field lines go from the north to the south and the closer the field lines are, the stronger the force.

ELECTROMAGNETISM

Electric charges in motion crate magnetic fields.

MOTORS

a device that converts electric energy into kinetic energy.

GENERATORS

A device that converts kinetic energy into electric energy

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ELECTRICAL ENERGY SOURCES

GENERATING ELECTRICAL POWER TURBINES

A power source turns a turbine which is a propeller-like piece that turns a metal shaft in an electric generator.

Examples: a hydropower plant uses falling water to turn the turbine. The spinning turbine converts kinetic energy into electricity.

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