Reviewer TLE 1st MT

A comprehensive set of question-and-answer flashcards covering electricity fundamentals, energy sources, Ohm’s Law, circuit components, and safety for TLE Grade 10 review.

What is electricity?

A form of energy produced by the movement of charged particles (typically electrons).

What are the two main forms of electricity and give an example of each.

Static electricity – stationary charges (e.g., lightning); Current electricity – flowing charges (e.g., power in household wiring).

Which two fundamental sets of equations govern electricity?

Ohm’s Law (V = I × R) and Maxwell’s Equations.

State Ohm’s Law.

The current through a conductor is directly proportional to the voltage across it and inversely proportional to its resistance (V = I × R).

Give the variables and units in the Ohm’s Law formula V = I × R.

V = voltage (volts, V); I = current (amperes, A); R = resistance (ohms, Ω).

List three ways electricity has revolutionized daily life.

Electric lighting, operation of household appliances, and enabling modern communication (phones, internet, TV, radio).

Name three sectors where electricity drives economic growth.

Manufacturing/industry, information technology, and transportation.

How is coal used to generate electricity?

It is burned to produce steam that spins turbines connected to generators.

Give one advantage and one disadvantage of coal power.

Advantage: reliable with high energy output; Disadvantage: major CO₂ emissions and air pollution.

Why is natural gas considered cleaner than coal?

It emits less CO₂ per unit of energy and gas turbines are highly efficient.

Provide one pro and one con of using oil to generate electricity.

Pro: high energy density and portability; Con: expensive and highly polluting, being phased out.

How does nuclear power generate electricity?

Heat from uranium fission turns water into steam that drives turbines.

State one benefit and one drawback of nuclear power.

Benefit: very low CO₂ emissions with high, reliable output; Drawback: radioactive waste and high initial cost.

What is the basic principle behind hydropower?

Flowing or falling water spins turbines to generate electricity.

Give one advantage and one limitation of hydropower.

Advantage: clean, reliable, and can store energy (pumped hydro); Limitation: ecological disruption and dependence on local geography.

How do wind turbines create electricity?

Wind turns the blades, which rotate a generator to produce electric power.

State one advantage and one challenge of wind power.

Advantage: zero emissions and low operating cost; Challenge: intermittent output and land/space requirements.

How do photovoltaic (PV) cells work?

They convert sunlight directly into electrical energy via the photovoltaic effect.

Provide one pro and one con of solar power.

Pro: abundant, silent, low maintenance; Con: intermittent (needs sunlight) and requires energy storage.

What is biomass energy and how is it generated?

Energy from organic material that is burned or digested to produce electricity or biogas.

Name one environmental concern related to biomass power.

Potential deforestation and air pollution if feedstock is not sustainably sourced or burned efficiently.

Define geothermal energy.

Electricity produced from heat within the Earth’s crust, typically via steam-driven turbines.

Give an example of an emerging future electricity source and why it is promising.

Nuclear fusion – it could offer abundant, low-carbon energy without long-lived radioactive waste.

Which electricity sources have zero direct CO₂ emissions?

Wind power and solar power (with nuclear having very low indirect emissions).

In the comparison table, which non-renewable source has very low CO₂ emissions?

Nuclear power.

Summarize the global trend in electricity generation.

A transition from coal and natural gas toward rapidly growing solar and wind, with interest in low-carbon options like nuclear, hydrogen, and fusion.

Define voltage.

The electric potential difference between two points; the ‘push’ that drives current (measured in volts).

Define current.

The rate of flow of electric charge through a conductor (measured in amperes).

Define resistance.

A material’s opposition to the flow of electric current (measured in ohms).

According to Ohm’s Law, what happens to current if voltage increases while resistance stays constant?

Current increases proportionally.

What three components are required for any electric circuit?

A power source, a conductive path, and a load.

Describe a series circuit.

A circuit with one path for current; the same current flows through all components.

What is a major disadvantage of series circuits?

If one component fails, the entire circuit stops working.

Describe a parallel circuit and its main advantage.

Multiple current paths with equal voltage across branches; one component can fail without stopping others.

Which circuit type combines series and parallel arrangements?

A series-parallel (compound) circuit.

State Kirchhoff’s Current Law (KCL).

The sum of currents entering a junction equals the sum of currents leaving the junction.

State Kirchhoff’s Voltage Law (KVL).

The algebraic sum of all voltages around a closed loop equals the source voltage.

What is a short circuit and why is it dangerous?

An unintended low-resistance path that allows excessive current, risking heat, fire, or equipment damage.

Name two common circuit protection devices.

Fuses and circuit breakers.

Which instrument measures electric current?

An ammeter.

How do fuses and circuit breakers differ?

A fuse melts once and must be replaced; a circuit breaker trips but can be reset.

What is the purpose of grounding in an electrical system?

It provides a zero-volt reference and a safe path for fault currents to protect users from electric shock.

Write the basic power formula related to Ohm’s Law variables.

P = V × I (power equals voltage times current).