Unit 3 Science 9

What is electrical energy?

Electrical energy is the energy of charged particles.

What uses electrical energy?

The human body (muscle and nerve signals), and technology (touch screens, robots).

How is energy transformed?

Energy is not created or destroyed, it is transformed from one form to another.

What is mechanical energy?

A combination of kinetic (motion) and potential (stored) energy.

What is chemical energy?

Energy stored in chemical bonds, released during chemical reactions (e.g., fossil fuels, biomass).

What is solar energy?

Energy carried by electromagnetic radiation from the Sun.

What is nuclear energy?

Energy created by forming new atoms via fusion or fission.

What is thermal energy?

Energy from fast-moving particles; detected as heat.

How is most of Canada’s electricity generated?

By transforming kinetic energy (e.g., moving water, steam, wind) into electrical energy.

What is a generator system?

A system with a turbine, shaft, and generator that converts kinetic energy into electrical energy.

How does hydroelectric energy work?

Water behind a dam flows downhill, turns a turbine connected to a generator.

How do fossil fuel stations generate electricity?

Thermal energy from burning coal creates steam, which turns turbines.

How do nuclear reactors generate electricity?

Fission reactions release heat, boiling water into steam that turns turbines.

How does wind generate electricity?

Wind turns turbines, converting kinetic energy into electrical energy.

What is an anemometer?

A device that measures wind speed.

How does solar energy become electricity?

Photovoltaic cells convert visible light into electrical energy.

How does geothermal energy generate electricity?

Steam from Earth's interior turns turbines.

How can tides and waves generate electricity?

Their movement turns turbines.

What charge do electrons carry?

Negative.

What charge do protons carry?

Positive.

What happens when opposite charges meet?

They attract.

What happens when like charges meet?

They repel.

How does rubbing two materials cause charge?

Electrons are transferred, making one material positive and the other negative.

What is an uncharged object?

An object with equal protons and electrons (electrically neutral).

What is a charged object?

An object with an uneven number of protons and electrons.

Law of Electric Charge

Opposite charges attract; like charges repel.

Why does a balloon stick to a neutral wall?

Negative charges in the balloon push wall electrons away, exposing protons which attract the balloon.

What is an electrochemical cell?

A device that transforms chemical energy into electrical energy (e.g., AA battery).

What are electrodes?

Metals where chemical reactions occur in a cell.

What is an electrolyte?

The solution in which electrodes are placed.

What is a battery?

A combination of 2 or more electrochemical cells.

How does a cell work?

Chemical reactions separate charges; electrons gather at the negative terminal, protons stay at the positive.

What is electrical potential difference (voltage)?

The energy per unit of charge gained when passing through a source; measured in volts (V).

What is conductivity?

How easily electrical charges move through a material.

What is a conductor?

A material that allows electrical charges to pass through easily (e.g., metals).

What is an insulator?

A material that does not allow charges to pass through easily.

What is current (I)?

The flow of electrical charges; measured in amperes (A).

What is a load?

A device that converts electrical energy into another form (e.g., light bulb, radio).

What is resistance (R)?

The amount a load resists current flow; measured in ohms (Ω).

What is an electrical circuit?

A closed loop with a source, load, and wires that allows current to flow.

What is a short circuit?

A low-resistance circuit that allows dangerously high current to flow.

What does a switch do?

Controls current flow: open = no flow; closed = current flows.

What symbol represents a cell?

||

What symbol represents a battery?

|‖|

What symbol represents a wire?

———

What symbol represents a load?

Ω

What symbol represents an open switch?

/‖

What symbol represents a closed switch?

——‖——

What is the formula for voltage?

V = I × R

What does each variable in V = IR mean?

V = voltage, I = current, R = resistance.

What is a series circuit?

A circuit with only one path for current to flow through.

What is a parallel circuit?

A circuit with two or more paths for current to flow.

Why are series circuits impractical for homes?

If one component fails, the whole circuit stops working.

What happens to current in a parallel circuit?

It splits across different branches but the total current stays the same.

What units measure electrical energy?

Watts (W), kilowatts (kW), kilowatt-hours (kWh).

What is electrical power?

The rate at which energy is used; measured in watts (W) or kilowatts (kW).

How do you calculate energy use?

Energy (kWh) = Power (kW) × Time (hours).

What does a smart meter do?

Measures how energy use changes over the day and sends data wirelessly to utility companies.

What is an EnerGuide label?

A label showing how much energy an appliance uses in one year.

What is the ENERGY STAR label?

Identifies appliances that are energy efficient (use 10–50% less energy).

What is phantom load?

Electrical energy used by a device when it is turned off (e.g., stand-by mode).

What are non-renewable energy sources?

Energy sources that cannot be replaced in a human lifetime (e.g., fossil fuels).

What are renewable energy sources?

Energy sources available continuously (e.g., wind, sun, rivers, biomass, geothermal).

What is the WAC Bennett Dam?

A hydroelectric dam on the Peace River that provides most of BC’s electricity.

What is Bear Mountain Wind Park?

A wind energy project that generates 144 MW using 34 wind turbines.

How can we use energy sustainably?

Use safe, renewable energy; reduce reliance on fossil fuels; ensure future access.

What is First Peoples’ Ecosystem Based Management (EBM)?

A decision-making approach that respects nature, shares knowledge, and considers future impacts.