Which device converts electrical energy into mechanical energy?
a) Transformer
b) Generator
c) Motor
d) Capacitor
What is the primary function of a transformer?
a) Convert DC to AC
b) Increase or decrease voltage
c) Store electrical energy
d) Generate electricity
Which of the following uses electromagnets?
a) Electric bells
b) Solar panels
c) Gas stoves
d) Thermometers
MRI (Magnetic Resonance Imaging) in medical applications relies on which property?
a) Gravitational force
b) Magnetic fields and radio waves
c) Optical refraction
d) Thermal conductivity
What is the working principle of an electric generator?
a) Chemical reaction
b) Electromagnetic induction
c) Heat transfer
d) Nuclear reaction
Which component in power transmission reduces energy loss?
a) Resistors
b) Inductors
c) Transformers
d) Capacitors
Which law describes the force between two charges?
a) Ohm’s Law
b) Newton’s Law
c) Coulomb’s Law
d) Faraday’s Law
Which everyday device uses induction heating?
a) Microwave oven
b) Induction cooktop
c) Refrigerator
d) Television
What is the purpose of a lightning rod?
a) Store electrical charge
b) Convert electricity to heat
c) Provide a safe path for lightning discharge
d) Generate electricity
Which of the following is based on the Hall Effect?
a) Smoke detectors
b) Magnetic field sensors
c) Incandescent bulbs
d) Wind turbines
Which device converts mechanical energy into electrical energy?
a) Transformer
b) Motor
c) Generator
d) Resistor
What is the primary function of a capacitor in electrical circuits?
a) Store charge
b) Increase voltage
c) Convert AC to DC
d) Generate electricity
What does a solenoid do when current flows through it?
a) Produces heat
b) Creates a magnetic field
c) Increases resistance
d) Converts AC to DC
Which phenomenon is responsible for transformers working?
a) Photoelectric effect
b) Electromagnetic induction
c) Superconductivity
d) Magnetic resonance
What is an application of superconductors?
a) High-speed maglev trains
b) Incandescent lamps
c) Normal electrical wiring
d) Gas stoves
What type of wave is used in radio transmission?
a) Sound waves
b) Mechanical waves
c) Electromagnetic waves
d) Gravitational waves
Which household appliance uses a motor?
a) Ceiling fan
b) LED bulb
c) Microwave oven
d) Solar panel
Which material is commonly used for electrical wiring?
a) Iron
b) Copper
c) Plastic
d) Wood
What is the function of an inductor in a circuit?
a) Store energy in a magnetic field
b) Convert DC to AC
c) Increase resistance
d) Generate electricity
Why are power lines operated at high voltage?
a) To reduce power loss
b) To increase current
c) To improve efficiency of appliances
d) To store energy
Which device protects electrical circuits from overcurrent?
a) Capacitor
b) Fuse
c) Resistor
d) Transformer
What principle does a microphone work on?
a) Sound amplification
b) Electromagnetic induction
c) Photoelectric effect
d) Thermionic emission
How does a relay switch operate?
a) By increasing resistance
b) By using an electromagnet to open/close a circuit
c) By storing electrical energy
d) By converting AC to DC
Which device is used to measure current?
a) Voltmeter
b) Ammeter
c) Ohmmeter
d) Hydrometer
What is the purpose of an alternator in vehicles?
a) Convert mechanical energy to electrical energy
b) Store electrical energy
c) Convert AC to DC
d) Increase voltage
What kind of motor is used in electric vehicles?
a) Diesel engine
b) AC/DC motor
c) Gas turbine
d) Hydraulic motor
Which of the following is a renewable energy source based on electromagnetic principles?
a) Fossil fuels
b) Wind turbines
c) Nuclear reactors
d) Geothermal plants
Which of these is a direct application of electromagnetism?
a) Hydraulic brakes
b) MRI scanners
c) Mechanical pulleys
d) Solar panels
How do electric trains work?
a) By using fossil fuels
b) By using electromagnetic induction and motors
c) By chemical combustion
d) By nuclear reaction
What is the purpose of a rectifier?
a) Convert AC to DC
b) Increase current
c) Decrease voltage
d) Convert DC to AC
