Electricity & Magnetism MCQs 2026

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

1. AResistor✓
2. BCapacitor✓
3. CDiode✓
4. DTransistor✓

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

1. ATransformer✓
2. BFuse/Circuit breaker✓
3. CCapacitor✓
4. DResistor✓

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

1. AOpen circuit✓
2. BClosed circuit✓
3. CBroken circuit✓
4. DIsolated circuit✓

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

1. AOpen circuit✓
2. BClosed circuit✓
3. CShort circuit✓
4. DParallel circuit✓

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

1. AVoltage remains the same across each branch✓
2. BVoltage increases progressively✓
3. CVoltage decreases progressively✓
4. DVoltage becomes zero✓

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

1. ACurrent remains the same throughout✓
2. BCurrent increases at each component✓
3. CCurrent decreases at each component✓
4. DCurrent varies unpredictably✓

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

1. ASeries circuit✓
2. BParallel circuit✓
3. COpen circuit✓
4. DShort circuit✓

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

1. ASeries circuit✓
2. BParallel circuit✓
3. COpen circuit✓
4. DShort circuit✓

What is the mathematical formula for Ohm's Law

1. AV = IR✓
2. BV = I/R✓
3. CV = I + R✓
4. DV = I - R✓

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

1. AConductors✓
2. BInsulators✓
3. CSemiconductors✓
4. DSuperconductors✓

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

1. AOpen circuit✓
2. BClosed circuit✓
3. CShort circuit✓
4. DSeries circuit✓

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

1. ACircuit breaker✓
2. BLightning rod✓
3. CFuse✓
4. DSurge protector (related, but for smaller-scale protection)✓

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

1. AA few hundred volts✓
2. BA few thousand volts✓
3. CTens of millions of volts✓
4. DA 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. AAurora✓
2. BLightning✓
3. CRainbow✓
4. DSolar flare✓

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

1. AProduct of charges, inversely proportional to distance squared✓
2. BSum of charges, directly proportional to distance✓
3. CProduct of charges, directly proportional to distance✓
4. DDifference of charges only✓

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

1. AConductors✓
2. BInsulators✓
3. CSemiconductors✓
4. DSuperconductors✓

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

1. AMichael Faraday✓
2. BCharles-Augustin de Coulomb✓
3. CJames Clerk Maxwell✓
4. DHans Christian Oersted✓

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

1. AElectric field✓
2. BMagnetic field✓
3. CGravitational field✓
4. DNuclear field✓

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

1. AElectric field✓
2. BMagnetic field✓
3. CGravitational field✓
4. DNuclear field✓

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

1. AHans Christian Oersted✓
2. BMichael Faraday✓
3. CJames Clerk Maxwell✓
4. DNikola Tesla✓

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

1. AHans Christian Oersted✓
2. BMichael Faraday✓
3. CJames Clerk Maxwell✓
4. DNikola Tesla✓

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

1. AHans Christian Oersted✓
2. BMichael Faraday✓
3. CJames Clerk Maxwell✓
4. DAndre-Marie Ampere✓

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

1. AGenerator (opposite function)✓
2. BElectric motor✓
3. CTransformer (different function)✓
4. DCapacitor (different function)✓

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

1. AElectric motor (opposite function)✓
2. BGenerator✓
3. CTransformer (different function)✓
4. DBattery (different mechanism)✓

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

1. AMotor✓
2. BGenerator✓
3. CTransformer✓
4. DCapacitor✓

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

1. AResistor✓
2. BCapacitor✓
3. CInductor✓
4. DDiode✓

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

1. ACapacitor✓
2. BResistor✓
3. CTransformer✓
4. DTransistor (different, more complex function)✓

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

1. AResistor✓
2. BCapacitor✓
3. CDiode✓
4. DTransformer✓

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

1. AAlternating current (AC)✓
2. BDirect current (DC)✓
3. CInduced current (general term)✓
4. DStatic current (not standard terminology)✓

What is the SI unit for measuring total electric charge

1. AAmpere✓
2. BVolt✓
3. CCoulomb✓
4. DOhm✓

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

1. AAlternating current (AC)✓
2. BDirect current (DC)✓
3. CInduced current (general term)✓
4. DStatic current✓

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

1. AThomas Edison (DC proponent)✓
2. BNikola Tesla✓
3. CBenjamin Franklin✓
4. DMichael Faraday✓

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

1. AWar of Currents✓
2. BSpace Race (unrelated)✓
3. CIndustrial Revolution (broader era)✓
4. DInformation 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. ACurrent electricity✓
2. BStatic electricity✓
3. CInduced electricity✓
4. DAlternating electricity✓

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

1. AStatic electricity buildup and discharge✓
2. BAlternating current effects✓
3. CElectromagnetic induction✓
4. DMagnetic attraction (unrelated mechanism)✓

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

1. ACoulomb (unit of total charge, not per-electron)✓
2. BElementary charge✓
3. CAmpere (unit of current, not charge)✓
4. DVolt (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. AConductors✓
2. BInsulators✓
3. CSemiconductors✓
4. DSuperconductors✓

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

1. AOhm's Law✓
2. BNewton's Law✓
3. CFaraday's Law✓
4. DCoulomb's Law✓

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

1. AVolt✓
2. BAmpere✓
3. COhm✓
4. DWatt✓

What is the SI unit of electrical resistance

1. AVolt✓
2. BAmpere✓
3. COhm✓
4. DWatt✓

What is the SI unit of electric current

1. AVolt✓
2. BAmpere✓
3. COhm✓
4. DWatt✓

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

1. AConductors✓
2. BInsulators✓
3. CSemiconductors✓
4. DSuperconductors✓

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

1. AEarth's magnetosphere✓
2. BEarth's atmosphere (different concept)✓
3. CEarth's ionosphere (related but distinct)✓
4. DEarth's ozone layer (different concept)✓

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

1. ASpeaker✓
2. BBattery (different function)✓
3. CResistor (different function)✓
4. DCapacitor (different function)✓

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

1. AElectromagnetic crane✓
2. BRefrigerator magnet (permanent magnet)✓
3. CCompass (permanent magnet)✓
4. DBar magnet toy (permanent magnet)✓

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

1. AIts magnetic field can be turned on/off and adjusted by controlling current✓
2. BIt never loses its magnetism✓
3. CIt requires no electricity✓
4. DIt 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. APermanent magnet✓
2. BElectromagnet✓
3. CNatural magnet✓
4. DBar magnet (a shape, not this classification)✓

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

1. AMagnetite (Lodestone)✓
2. BHematite (not naturally magnetic in the same way)✓
3. CQuartz✓
4. DPyrite✓

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

1. AThey attract each other✓
2. BThey repel each other✓
3. CThey neutralize each other✓
4. DNo interaction occurs✓

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

1. AThey attract each other✓
2. BThey repel each other✓
3. CThey neutralize each other✓
4. DNo interaction occurs✓

What term describes materials that are weakly repelled by magnetic fields

1. AFerromagnetic materials✓
2. BDiamagnetic materials✓
3. CParamagnetic materials✓
4. DSuperconducting materials (related, extreme diamagnetism)✓

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

1. AFerromagnetic materials✓
2. BDiamagnetic materials✓
3. CParamagnetic materials✓
4. DAntiferromagnetic materials (different, more complex behavior)✓

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

1. AVoltage✓
2. BCurrent✓
3. CPower✓
4. DResistance✓

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

1. APower = Voltage × Current✓
2. BPower = Voltage / Current✓
3. CPower = Voltage + Current✓
4. DPower = Voltage - Current✓

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

1. AWatt✓
2. BKilowatt-hour✓
3. CAmpere✓
4. DVolt✓

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

1. AEnsuring proper grounding and circuit isolation before working on components✓
2. BNo precautions are necessary for household circuits✓
3. CWorking on live circuits is always safe with proper footwear alone✓
4. DOnly voltage matters, not current, for safety✓

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

1. AFerromagnetic materials✓
2. BDiamagnetic materials✓
3. CParamagnetic materials✓
4. DNon-magnetic materials✓

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

1. APoles (North and South)✓
2. BNodes✓
3. CTerminals (electrical term, not magnetic)✓
4. DVertices✓

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

1. AMagnetic monopole✓
2. BBipole (not standard terminology)✓
3. CIsolated pole (not standard terminology)✓
4. DFree pole (not standard terminology)✓

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

1. ACompass✓
2. BGPS device (satellite-based, different mechanism)✓
3. CSextant (celestial navigation, different mechanism)✓
4. DBarometer (unrelated to navigation)✓

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

1. AMagnetic pole reversal✓
2. BContinental drift (unrelated geological process)✓
3. CPlate tectonics (unrelated process)✓
4. DVolcanic activity (unrelated process)✓

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

1. AAurora (Northern/Southern Lights)✓
2. BLightning✓
3. CRainbow✓
4. DSolar eclipse✓

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

1. AAlessandro Volta✓
2. BAndre-Marie Ampere✓
3. CGeorg Ohm✓
4. DMichael Faraday✓

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

1. AFrom positive to negative terminal✓
2. BFrom negative to positive terminal (actual electron flow direction)✓
3. CNo standard convention exists✓
4. DDepends 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. AGFCI (Ground Fault Circuit Interrupter)✓
2. BStandard fuse (different protective function)✓
3. CSimple circuit breaker (different, broader protective function)✓
4. DVoltage 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. ATransducers (general term)✓
2. BGenerators/Motors specifically (subtypes of transducers)✓
3. CBoth terms broadly relate to this energy conversion concept✓
4. DNeither term applies to this concept✓

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

1. ACapacitor✓
2. BBattery✓
3. CResistor✓
4. DTransformer✓

What are the two terminals of a battery called

1. APositive and negative terminals (anode and cathode)✓
2. BNorth and south poles (magnetic terminology, not battery)✓
3. CInput and output (general electronic terms)✓
4. DLive and neutral (household wiring terminology)✓

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

1. ALead-acid battery✓
2. BNickel-cadmium battery✓
3. CLithium-ion battery✓
4. DZinc-carbon battery✓

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

1. ALithium-ion battery✓
2. BLead-acid battery✓
3. CNickel-metal hydride battery✓
4. DZinc-carbon battery✓

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

1. AAlessandro Volta✓
2. BMichael Faraday✓
3. CThomas Edison✓
4. DBenjamin Franklin✓

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

1. AAlessandro Volta✓
2. BAndre-Marie Ampere✓
3. CGeorg Ohm✓
4. DJames Watt✓

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

1. AFrom negative to positive terminal✓
2. BFrom positive to negative terminal (conventional current direction, opposite actual electron flow)✓
3. CElectrons do not have a directional flow✓
4. DRandomly in all directions✓

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

1. AAlessandro Volta✓
2. BAndre-Marie Ampere✓
3. CGeorg Simon Ohm✓
4. DJames Watt✓

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

1. AJames Watt✓
2. BAlessandro Volta✓
3. CMichael Faraday✓
4. DNikola Tesla✓

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

1. ADiscovering that lightning is a form of electricity✓
2. BInventing the first battery✓
3. CDiscovering electromagnetic induction✓
4. DInventing the first electric motor✓

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

1. ACurrent electricity✓
2. BElectrostatics✓
3. CElectromagnetism (broader field encompassing both)✓
4. DElectrodynamics (related to charges in motion)✓

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

1. AElectrostatics✓
2. BCurrent electricity (general term)✓
3. CElectrodynamics✓
4. DBoth 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. APrimary battery (single-use)✓
2. BSecondary (rechargeable) battery✓
3. CAlkaline battery (typically single-use)✓
4. DZinc-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. APrimary battery✓
2. BSecondary (rechargeable) battery✓
3. CLithium-ion battery (typically rechargeable)✓
4. DNickel-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. AHigh-voltage transmission lines✓
2. BLow-voltage distribution lines (used closer to end consumers)✓
3. CHousehold wiring (much lower voltage, local use)✓
4. DTelephone 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. APower surge✓
2. BPower outage (opposite concept - loss of power)✓
3. CVoltage drop (opposite concept - decrease in voltage)✓
4. DGround fault (different specific issue)✓

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

1. APower grid (Electrical grid)✓
2. BWater supply network (unrelated)✓
3. CTelecommunications network (unrelated)✓
4. DRoad network (unrelated)✓

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

1. ASolar panels (Photovoltaic cells)✓
2. BWind turbines (different energy conversion)✓
3. CHydroelectric generators (different energy conversion)✓
4. DGeothermal plants (different energy conversion)✓

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

1. ASurge protector✓
2. BFuse (protects against overcurrent, different mechanism)✓
3. CCircuit breaker (protects against overcurrent, different mechanism)✓
4. DTransformer (changes voltage level, different purpose)✓

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

1. APower outage (Blackout)✓
2. BPower surge (opposite - excess voltage)✓
3. CBrownout (partial reduction, not complete loss)✓
4. DGround fault (different specific issue)✓

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

1. ABlackout (complete loss)✓
2. BBrownout✓
3. CPower surge (opposite - excess voltage)✓
4. DGround 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. ACapacitor (stores energy in electric field, not magnetic)✓
2. BInductor✓
3. CResistor (dissipates energy, does not store it)✓
4. DDiode (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. AHigh voltage transmission significantly reduces energy loss due to resistance in the wires✓
2. BHigh voltage is simply a historical convention with no technical benefit✓
3. CLow voltage transmission is illegal in most countries✓
4. DHigh 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. AMains voltage (Household supply voltage)✓
2. BTransmission voltage (much higher, for long-distance lines)✓
3. CBattery voltage (typically much lower)✓
4. DSignal voltage (used in electronics, typically very low)✓