Science 9 - Electrical Energy and Circuits

Flashcards covering the Science 9 curriculum on electricity, including types of energy, power generation, static charge, Ohm's law, circuits, and sustainability.

Electrical Energy

The energy of charged particles.

Mechanical Energy

The sum of kinetic energy and potential energy.

Kinetic Energy

Energy of motion.

Potential Energy

Stored energy that a system has due to its position or condition.

Chemical Energy

Energy stored in chemical bonds and released when a chemical reaction occurs.

Biomass

Chemical energy stored in animals and plants.

Solar Energy

Energy carried by electromagnetic radiation given off by the Sun.

Nuclear Fusion

New atoms are made as smaller atoms collide and fuse; this occurs in the Sun and stars.

Nuclear Fission

New atoms are made by splitting larger atoms, carried out in reactors on Earth.

Thermal Energy

Energy due to the rapid motion of particles that make up an object, detected as heat.

Generator System

A system that transforms kinetic energy into electrical energy.

Turbine

A component that steam, water, or wind cause to spin.

Photovoltaic Cells

Devices that transform the energy of visible light to electrical energy.

Static Charge (Static Electricity)

Electric charge that stays in one place until it is discharged to other objects or to the air.

Coulomb (C)

The unit of electric charge; it takes the addition or removal of $6.25 \times 10^{18}$ electrons to produce $1\text{C}$ of charge.

Insulators

Materials that do not allow electrons to move easily and can retain a static charge; examples include glass, plastics, and ceramics.

Conductors

Materials that allow electrons to move easily, such as metals.

Conductivity

An indication of how easily charges travel through a material.

Van de Graaff Generator

A device that uses friction to produce a large static charge on a metal dome.

Grounding

Connecting a conductor so that electric charge flows into Earth's surface.

Electric Force

A push or pull between charged objects (an action-at-a-distance force).

Laws of Static Charge

1. Like charges repel. 2. Opposite charges attract. 3. Neutral objects are attracted to charged objects.

Coulomb's Law

States that if the amount of charge increases, the electric force increases; if the distance increases, the electric force decreases.

Charging by Conduction

The process where objects become charged through contact, allowing electrons to move from one object to another.

Charging by Induction

The process where objects are charged without making direct contact; electrons reposition themselves temporarily.

Electrochemical Cells

Devices that convert chemical energy into electrical energy.

Battery

A single electrochemical cell or a combination of electrochemical cells connected together.

Electrode

Two terminals in an electrochemical cell/battery, usually made of different metals.

Electrolyte

A substance that conducts electricity, found inside an electrochemical cell as a moist paste (dry cell) or a liquid (wet cell).

Electric Potential Energy

The electrical energy stored in an electrochemical cell.

Voltage (Electric Potential Difference)

The amount of electric potential energy per coulomb of charge.

Volt (V)

The unit of measurement for voltage.

Voltmeter

A device used to measure voltage between two locations of charge separation.

Electric Circuit

A complete pathway that allows electrons to flow.

Source

A component where electrical energy comes from, such as an electrochemical cell or battery.

Load

A device that converts electrical energy into other forms of energy (e.g., light bulbs, heaters, radios).

Electric Current (I)

The amount of charge passing a point in a conductor every second.

Ampere (A)

The unit of measurement for electric current.

Ammeter

A device used to measure the current in a circuit.

Resistance (R)

The property of a material that slows down the flow of electrons and converts electrical energy into other forms of energy.

Ohm ($\Omega$)

The unit of measurement for resistance.

Ohm's Law

The mathematical relationship where $\text{Voltage (V)} = \text{Current (I)} \times \text{Resistance (R)}$.

Short Circuit

A circuit with a resistance that is too low, making the current so high it is dangerous.

Series Circuit

A circuit that has only one path for current to travel.

Parallel Circuit

A circuit that has more than one path for current to travel.

Junction Point

Where a circuit divides into multiple paths or where multiple paths join.

Electrical Power

The rate at which electrical energy is used by a load.

Watt (W)

The unit for measuring power, calculated as $\text{Power (P)} = \text{Voltage (V)} \times \text{Current (I)}$.

Kilowatt-hour (kW·h)

A unit of energy used for billing, calculated as $\text{Energy} = \text{Power} \times \text{Time}$.

Sustainable Energy System

A way of producing and using energy that has limited impact on environmental and human health, ensuring availability for future generations.