Electricity & Magnetism MCQs 2026

What semiconductor device can amplify or switch electronic signals, foundational to modern electronics

1. A Resistor ✓
2. B Capacitor ✓
3. C Diode ✓
4. D Transistor ✓

What safety device is designed to interrupt an electrical circuit automatically if current exceeds a safe level, preventing fires

1. A Transformer ✓
2. B Fuse/Circuit breaker ✓
3. C Capacitor ✓
4. D Resistor ✓

What term describes an electrical circuit with a complete path allowing current to flow continuously

1. A Open circuit ✓
2. B Closed circuit ✓
3. C Broken circuit ✓
4. D Isolated circuit ✓

What term describes a break in an electrical circuit that prevents current from flowing

1. A Open circuit ✓
2. B Closed circuit ✓
3. C Short circuit ✓
4. D Parallel circuit ✓

In a parallel circuit, what happens to the voltage across each parallel branch

1. A Voltage remains the same across each branch ✓
2. B Voltage increases progressively ✓
3. C Voltage decreases progressively ✓
4. D Voltage becomes zero ✓

In a series circuit, what happens to the current at every point along the circuit

1. A Current remains the same throughout ✓
2. B Current increases at each component ✓
3. C Current decreases at each component ✓
4. D Current varies unpredictably ✓

What type of electrical circuit provides multiple paths for current to flow

1. A Series circuit ✓
2. B Parallel circuit ✓
3. C Open circuit ✓
4. D Short circuit ✓

What type of electrical circuit provides only a single path for current to flow

1. A Series circuit ✓
2. B Parallel circuit ✓
3. C Open circuit ✓
4. D Short circuit ✓

What is the mathematical formula for Ohm's Law

1. A V = IR ✓
2. B V = I/R ✓
3. C V = I + R ✓
4. D V = I - R ✓

What is the term for materials that strongly resist the flow of electric current, such as rubber or glass

1. A Conductors ✓
2. B Insulators ✓
3. C Semiconductors ✓
4. D Superconductors ✓

What dangerous electrical condition occurs when current takes an unintended path with very low resistance, potentially causing overheating or fire

1. A Open circuit ✓
2. B Closed circuit ✓
3. C Short circuit ✓
4. D Series circuit ✓

What safety device, commonly installed on tall buildings, is designed to safely direct lightning strikes into the ground

1. A Circuit breaker ✓
2. B Lightning rod ✓
3. C Fuse ✓
4. D Surge protector (related, but for smaller-scale protection) ✓

Approximately how much electrical potential (voltage) can a typical lightning bolt carry

1. A A few hundred volts ✓
2. B A few thousand volts ✓
3. C Tens of millions of volts ✓
4. D A few billion volts (overestimate) ✓

What natural phenomenon results from a massive discharge of static electricity between clouds or between a cloud and the ground

1. A Aurora ✓
2. B Lightning ✓
3. C Rainbow ✓
4. D Solar flare ✓

Coulomb's Law describes the electrostatic force as being proportional to what factors

1. A Product of charges, inversely proportional to distance squared ✓
2. B Sum of charges, directly proportional to distance ✓
3. C Product of charges, directly proportional to distance ✓
4. D Difference of charges only ✓

What is the term for materials with electrical conductivity between conductors and insulators, such as silicon, used extensively in electronics

1. A Conductors ✓
2. B Insulators ✓
3. C Semiconductors ✓
4. D Superconductors ✓

Who is credited with formulating the fundamental law describing the electrostatic force between charged particles

1. A Michael Faraday ✓
2. B Charles-Augustin de Coulomb ✓
3. C James Clerk Maxwell ✓
4. D Hans Christian Oersted ✓

What term describes the invisible field surrounding a magnet or electric current, exerting force on other magnetic materials or moving charges

1. A Electric field ✓
2. B Magnetic field ✓
3. C Gravitational field ✓
4. D Nuclear field ✓

What term describes the invisible field surrounding a charged object, exerting force on other charged objects

1. A Electric field ✓
2. B Magnetic field ✓
3. C Gravitational field ✓
4. D Nuclear field ✓

What scientist discovered that an electric current produces a magnetic field, foundational to electromagnetism

1. A Hans Christian Oersted ✓
2. B Michael Faraday ✓
3. C James Clerk Maxwell ✓
4. D Nikola Tesla ✓

Which scientist discovered electromagnetic induction, the principle behind generators and transformers

1. A Hans Christian Oersted ✓
2. B Michael Faraday ✓
3. C James Clerk Maxwell ✓
4. D Nikola Tesla ✓

Which scientist developed comprehensive equations unifying electricity, magnetism, and light as manifestations of electromagnetism

1. A Hans Christian Oersted ✓
2. B Michael Faraday ✓
3. C James Clerk Maxwell ✓
4. D Andre-Marie Ampere ✓

What device converts electrical energy into mechanical motion, using electromagnetic principles

1. A Generator (opposite function) ✓
2. B Electric motor ✓
3. C Transformer (different function) ✓
4. D Capacitor (different function) ✓

What device converts mechanical motion into electrical energy, the opposite function of a motor

1. A Electric motor (opposite function) ✓
2. B Generator ✓
3. C Transformer (different function) ✓
4. D Battery (different mechanism) ✓

What device changes the voltage of an alternating current, commonly used in power distribution systems

1. A Motor ✓
2. B Generator ✓
3. C Transformer ✓
4. D Capacitor ✓

What device stores electrical energy in an electric field, commonly used in electronic circuits

1. A Resistor ✓
2. B Capacitor ✓
3. C Inductor ✓
4. D Diode ✓

What electronic component limits or controls the flow of electric current within a circuit

1. A Capacitor ✓
2. B Resistor ✓
3. C Transformer ✓
4. D Transistor (different, more complex function) ✓

What electronic component allows current to flow in only one direction, commonly used for rectification

1. A Resistor ✓
2. B Capacitor ✓
3. C Diode ✓
4. D Transformer ✓

What term describes current that flows consistently in one direction, such as from a battery

1. A Alternating current (AC) ✓
2. B Direct current (DC) ✓
3. C Induced current (general term) ✓
4. D Static current (not standard terminology) ✓

What is the SI unit for measuring total electric charge

1. A Ampere ✓
2. B Volt ✓
3. C Coulomb ✓
4. D Ohm ✓

What term describes current that periodically reverses direction, such as that supplied by household power outlets

1. A Alternating current (AC) ✓
2. B Direct current (DC) ✓
3. C Induced current (general term) ✓
4. D Static current ✓

Which historical figure is associated with pioneering AC (alternating current) power distribution systems, in rivalry with proponents of DC systems

1. A Thomas Edison (DC proponent) ✓
2. B Nikola Tesla ✓
3. C Benjamin Franklin ✓
4. D Michael Faraday ✓

What historical episode describes the competitive rivalry between proponents of AC and DC electrical power systems in the late 19th century

1. A War of Currents ✓
2. B Space Race (unrelated) ✓
3. C Industrial Revolution (broader era) ✓
4. D Information Age (unrelated, later era) ✓

What phenomenon describes the buildup of electric charge on the surface of objects, often causing small shocks or attracting lightweight materials

1. A Current electricity ✓
2. B Static electricity ✓
3. C Induced electricity ✓
4. D Alternating electricity ✓

What everyday phenomenon, involving static electricity, causes hair to stand up or clothes to stick together after using a dryer

1. A Static electricity buildup and discharge ✓
2. B Alternating current effects ✓
3. C Electromagnetic induction ✓
4. D Magnetic attraction (unrelated mechanism) ✓

What is the term for the basic unit of electric charge carried by a single electron

1. A Coulomb (unit of total charge, not per-electron) ✓
2. B Elementary charge ✓
3. C Ampere (unit of current, not charge) ✓
4. D Volt (unit of potential, not charge) ✓

What is the term for materials that, under certain conditions (often very low temperatures), conduct electricity with zero resistance

1. A Conductors ✓
2. B Insulators ✓
3. C Semiconductors ✓
4. D Superconductors ✓

What law states the relationship between voltage, current, and resistance in an electrical circuit

1. A Ohm's Law ✓
2. B Newton's Law ✓
3. C Faraday's Law ✓
4. D Coulomb's Law ✓

What is the SI unit of electrical potential difference (voltage)

1. A Volt ✓
2. B Ampere ✓
3. C Ohm ✓
4. D Watt ✓

What is the SI unit of electrical resistance

1. A Volt ✓
2. B Ampere ✓
3. C Ohm ✓
4. D Watt ✓

What is the SI unit of electric current

1. A Volt ✓
2. B Ampere ✓
3. C Ohm ✓
4. D Watt ✓

What is the term for materials that allow electric current to flow through them easily, such as metals

1. A Conductors ✓
2. B Insulators ✓
3. C Semiconductors ✓
4. D Superconductors ✓

What is the term for Earth's natural magnetic field, which extends into space and protects against solar radiation

1. A Earth's magnetosphere ✓
2. B Earth's atmosphere (different concept) ✓
3. C Earth's ionosphere (related but distinct) ✓
4. D Earth's ozone layer (different concept) ✓

What everyday device relies on electromagnetic principles to convert electrical signals into sound

1. A Speaker ✓
2. B Battery (different function) ✓
3. C Resistor (different function) ✓
4. D Capacitor (different function) ✓

What common household or industrial device relies on electromagnets for its basic operation, such as lifting scrap metal

1. A Electromagnetic crane ✓
2. B Refrigerator magnet (permanent magnet) ✓
3. C Compass (permanent magnet) ✓
4. D Bar magnet toy (permanent magnet) ✓

What is a key advantage of an electromagnet compared to a permanent magnet

1. A Its magnetic field can be turned on/off and adjusted by controlling current ✓
2. B It never loses its magnetism ✓
3. C It requires no electricity ✓
4. D It is always weaker than permanent magnets ✓

What is the term for a magnet created by passing electric current through a coiled wire, often around an iron core

1. A Permanent magnet ✓
2. B Electromagnet ✓
3. C Natural magnet ✓
4. D Bar magnet (a shape, not this classification) ✓

What natural material, an iron oxide compound, is a naturally occurring magnet

1. A Magnetite (Lodestone) ✓
2. B Hematite (not naturally magnetic in the same way) ✓
3. C Quartz ✓
4. D Pyrite ✓

What happens when two like magnetic poles (North-North or South-South) are brought close together

1. A They attract each other ✓
2. B They repel each other ✓
3. C They neutralize each other ✓
4. D No interaction occurs ✓

What happens when two unlike magnetic poles (North-South) are brought close together

1. A They attract each other ✓
2. B They repel each other ✓
3. C They neutralize each other ✓
4. D No interaction occurs ✓

What term describes materials that are weakly repelled by magnetic fields

1. A Ferromagnetic materials ✓
2. B Diamagnetic materials ✓
3. C Paramagnetic materials ✓
4. D Superconducting materials (related, extreme diamagnetism) ✓

What term describes materials that are weakly attracted to magnetic fields, though far less strongly than ferromagnetic materials

1. A Ferromagnetic materials ✓
2. B Diamagnetic materials ✓
3. C Paramagnetic materials ✓
4. D Antiferromagnetic materials (different, more complex behavior) ✓

What is the term for the electrical power consumed or produced by a device, measured in watts

1. A Voltage ✓
2. B Current ✓
3. C Power ✓
4. D Resistance ✓

What is the mathematical formula relating electrical power to voltage and current

1. A Power = Voltage × Current ✓
2. B Power = Voltage / Current ✓
3. C Power = Voltage + Current ✓
4. D Power = Voltage - Current ✓

What is the unit commonly used by electricity providers to bill for energy consumption

1. A Watt ✓
2. B Kilowatt-hour ✓
3. C Ampere ✓
4. D Volt ✓

What safety precaution is essential when working with electrical circuits to prevent electric shock

1. A Ensuring proper grounding and circuit isolation before working on components ✓
2. B No precautions are necessary for household circuits ✓
3. C Working on live circuits is always safe with proper footwear alone ✓
4. D Only voltage matters, not current, for safety ✓

What term describes materials, like iron, that are strongly attracted to magnets and can themselves become magnetized

1. A Ferromagnetic materials ✓
2. B Diamagnetic materials ✓
3. C Paramagnetic materials ✓
4. D Non-magnetic materials ✓

What is the term for the two ends of a magnet, where magnetic force is strongest

1. A Poles (North and South) ✓
2. B Nodes ✓
3. C Terminals (electrical term, not magnetic) ✓
4. D Vertices ✓

What is the term for the theoretical single magnetic pole that has never been experimentally confirmed to exist independently

1. A Magnetic monopole ✓
2. B Bipole (not standard terminology) ✓
3. C Isolated pole (not standard terminology) ✓
4. D Free pole (not standard terminology) ✓

What everyday navigational device relies on Earth's magnetic field to indicate direction

1. A Compass ✓
2. B GPS device (satellite-based, different mechanism) ✓
3. C Sextant (celestial navigation, different mechanism) ✓
4. D Barometer (unrelated to navigation) ✓

What term describes the gradual, periodic reversal of Earth's magnetic poles over geological timescales

1. A Magnetic pole reversal ✓
2. B Continental drift (unrelated geological process) ✓
3. C Plate tectonics (unrelated process) ✓
4. D Volcanic activity (unrelated process) ✓

What natural phenomenon results from charged particles from the Sun interacting with Earth's magnetosphere near the poles

1. A Aurora (Northern/Southern Lights) ✓
2. B Lightning ✓
3. C Rainbow ✓
4. D Solar eclipse ✓

The unit of electric current, the "Ampere," is named after which scientist

1. A Alessandro Volta ✓
2. B Andre-Marie Ampere ✓
3. C Georg Ohm ✓
4. D Michael Faraday ✓

What is the historical convention for the direction of "conventional current" in circuit diagrams, despite actual electron flow being opposite

1. A From positive to negative terminal ✓
2. B From negative to positive terminal (actual electron flow direction) ✓
3. C No standard convention exists ✓
4. D Depends entirely on the specific circuit ✓

What safety device, commonly used in modern electrical outlets, detects imbalances in current flow to prevent electric shock, especially near water

1. A GFCI (Ground Fault Circuit Interrupter) ✓
2. B Standard fuse (different protective function) ✓
3. C Simple circuit breaker (different, broader protective function) ✓
4. D Voltage regulator (different function) ✓

What is the general term for devices that convert one form of energy into electrical energy, or vice versa, based on various physical principles

1. A Transducers (general term) ✓
2. B Generators/Motors specifically (subtypes of transducers) ✓
3. C Both terms broadly relate to this energy conversion concept ✓
4. D Neither term applies to this concept ✓

What is the term for a device that stores and releases electrical energy through chemical reactions

1. A Capacitor ✓
2. B Battery ✓
3. C Resistor ✓
4. D Transformer ✓

What are the two terminals of a battery called

1. A Positive and negative terminals (anode and cathode) ✓
2. B North and south poles (magnetic terminology, not battery) ✓
3. C Input and output (general electronic terms) ✓
4. D Live and neutral (household wiring terminology) ✓

Which type of rechargeable battery technology is most commonly used in modern smartphones and laptops

1. A Lead-acid battery ✓
2. B Nickel-cadmium battery ✓
3. C Lithium-ion battery ✓
4. D Zinc-carbon battery ✓

Which type of battery technology is most commonly used in traditional automobile starting systems

1. A Lithium-ion battery ✓
2. B Lead-acid battery ✓
3. C Nickel-metal hydride battery ✓
4. D Zinc-carbon battery ✓

Who is credited with inventing the first true electric battery, known as the "voltaic pile"

1. A Alessandro Volta ✓
2. B Michael Faraday ✓
3. C Thomas Edison ✓
4. D Benjamin Franklin ✓

The unit of electrical potential, the "Volt," is named after which scientist

1. A Alessandro Volta ✓
2. B Andre-Marie Ampere ✓
3. C Georg Ohm ✓
4. D James Watt ✓

What is the term for the specific direction electrons actually flow in a conventional electric circuit

1. A From negative to positive terminal ✓
2. B From positive to negative terminal (conventional current direction, opposite actual electron flow) ✓
3. C Electrons do not have a directional flow ✓
4. D Randomly in all directions ✓

The unit of electrical resistance, the "Ohm," is named after which scientist

1. A Alessandro Volta ✓
2. B Andre-Marie Ampere ✓
3. C Georg Simon Ohm ✓
4. D James Watt ✓

The unit of power, the "Watt," is named after which scientist known for steam engine improvements

1. A James Watt ✓
2. B Alessandro Volta ✓
3. C Michael Faraday ✓
4. D Nikola Tesla ✓

Benjamin Franklin is famously (though with some historical debate about exact methods) associated with which electrical experiment involving a kite

1. A Discovering that lightning is a form of electricity ✓
2. B Inventing the first battery ✓
3. C Discovering electromagnetic induction ✓
4. D Inventing the first electric motor ✓

What term describes the general study of stationary electric charges and their effects, as opposed to charges in motion

1. A Current electricity ✓
2. B Electrostatics ✓
3. C Electromagnetism (broader field encompassing both) ✓
4. D Electrodynamics (related to charges in motion) ✓

What term describes the general study of electric charges in motion, encompassing electric current and its effects

1. A Electrostatics ✓
2. B Current electricity (general term) ✓
3. C Electrodynamics ✓
4. D Both current electricity and electrodynamics are related terms for this concept ✓

What type of battery can be recharged and reused multiple times, such as those in smartphones

1. A Primary battery (single-use) ✓
2. B Secondary (rechargeable) battery ✓
3. C Alkaline battery (typically single-use) ✓
4. D Zinc-carbon battery (typically single-use) ✓

What type of battery is designed for single use and cannot be effectively recharged, such as many household alkaline batteries

1. A Primary battery ✓
2. B Secondary (rechargeable) battery ✓
3. C Lithium-ion battery (typically rechargeable) ✓
4. D Nickel-metal hydride battery (typically rechargeable) ✓

What term describes electrical power lines that transmit electricity at very high voltages over long distances, minimizing energy loss

1. A High-voltage transmission lines ✓
2. B Low-voltage distribution lines (used closer to end consumers) ✓
3. C Household wiring (much lower voltage, local use) ✓
4. D Telephone lines (unrelated to power transmission) ✓

What is the term for a temporary, uncontrolled increase in voltage within an electrical circuit, potentially damaging connected devices

1. A Power surge ✓
2. B Power outage (opposite concept - loss of power) ✓
3. C Voltage drop (opposite concept - decrease in voltage) ✓
4. D Ground fault (different specific issue) ✓

What is the term for the electrical grid infrastructure that distributes electricity from power plants to homes and businesses

1. A Power grid (Electrical grid) ✓
2. B Water supply network (unrelated) ✓
3. C Telecommunications network (unrelated) ✓
4. D Road network (unrelated) ✓

What is the term for solar cells that directly convert sunlight into electrical energy using the photovoltaic effect

1. A Solar panels (Photovoltaic cells) ✓
2. B Wind turbines (different energy conversion) ✓
3. C Hydroelectric generators (different energy conversion) ✓
4. D Geothermal plants (different energy conversion) ✓

What device is commonly used to protect sensitive electronics from power surges by limiting excess voltage

1. A Surge protector ✓
2. B Fuse (protects against overcurrent, different mechanism) ✓
3. C Circuit breaker (protects against overcurrent, different mechanism) ✓
4. D Transformer (changes voltage level, different purpose) ✓

What term describes a complete, temporary loss of electrical power supply to a specific area

1. A Power outage (Blackout) ✓
2. B Power surge (opposite - excess voltage) ✓
3. C Brownout (partial reduction, not complete loss) ✓
4. D Ground fault (different specific issue) ✓

What term describes a partial reduction in voltage supply, often causing lights to dim, without a complete power loss

1. A Blackout (complete loss) ✓
2. B Brownout ✓
3. C Power surge (opposite - excess voltage) ✓
4. D Ground fault (different specific issue) ✓

What is the term for a circuit component that stores energy in a magnetic field when current flows through it, typically a coil of wire

1. A Capacitor (stores energy in electric field, not magnetic) ✓
2. B Inductor ✓
3. C Resistor (dissipates energy, does not store it) ✓
4. D Diode (controls current direction, does not store energy) ✓

Why is electricity typically transmitted at very high voltages over long distances before being stepped down for household use

1. A High voltage transmission significantly reduces energy loss due to resistance in the wires ✓
2. B High voltage is simply a historical convention with no technical benefit ✓
3. C Low voltage transmission is illegal in most countries ✓
4. D High voltage is required to prevent theft of electricity ✓

What is the term for the standard voltage supplied to typical household outlets in most of the world (varies by country, but common examples include 120V or 230V)

1. A Mains voltage (Household supply voltage) ✓
2. B Transmission voltage (much higher, for long-distance lines) ✓
3. C Battery voltage (typically much lower) ✓
4. D Signal voltage (used in electronics, typically very low) ✓