Which instrument measures electrical current directly?
A Voltmeter
B Ammeter
C Wattmeter
D Galvanometer
Ammeters are designed to measure the flow of electric current in amperes by being connected in series with the circuit.
What type of transformer is used to measure high currents in power systems?
A Auto transformer
B Current transformer
C Distribution transformer
D Potential transformer
Current transformers step down high currents to lower levels suitable for measurement and protection in electrical circuits.
Which device is used to measure phase difference between two AC signals?
A Oscilloscope
B Phase meter
C Wattmeter
D Multimeter
Phase meters are used to measure the phase difference between two AC signals, expressed in degrees.
What does a tachometer measure?
A Voltage
B Speed of rotation
C Resistance
D Inductance
Tachometers are instruments that measure the rotational speed of an object, commonly in revolutions per minute (RPM).
What is the principle of operation of a piezoelectric transducer?
A Resistance change with temperature
B Electrical voltage generated under mechanical stress
C Magnetic induction
D Capacitance variation
Piezoelectric transducers generate electrical signals when subjected to mechanical stress, utilizing the piezoelectric effect.
What is the purpose of a galvanometer?
A Measure current
B Measure small currents
C Measure voltage
D Measure power
Galvanometers are sensitive instruments used to measure small electrical currents, typically in microamperes.
Which bridge is used to measure inductance?
A Schering bridge
B Maxwell bridge
C Kelvin bridge
D Wheatstone bridge
Maxwell bridges are designed for precise measurement of inductance in AC circuits.
What does a frequency meter measure?
A Voltage
B Frequency of AC signals
C Current
D Energy consumption
Frequency meters measure the frequency (number of cycles per second) of an AC signal, expressed in Hertz (Hz).
Which transducer is used for temperature measurement?
A Strain gauge
B Thermocouple
C LVDT
D Pressure sensor
Thermocouples measure temperature by generating a voltage based on the temperature difference between two junctions.
What is the principle of a current transformer (CT)?
A Electromagnetic induction
B Electromagnetic induction to step down current
C Capacitive effect
D Piezoelectric effect
Current transformers use electromagnetic induction to step down high current to lower levels suitable for measuring and protection.
Which material is most commonly used in a galvanometer coil?
A Copper
B Aluminum
C Iron
D Steel
Galvanometers typically use coils made from aluminum due to its low weight and high conductivity.
What does an oscillograph measure?
A Frequency
B Time-dependent electrical signals
C Power consumption
D Current levels
Oscillographs are used to measure time-dependent electrical signals, typically represented as waveforms.
What does a pressure transducer measure?
A Flow rate
B Pressure
C Displacement
D Speed
Pressure transducers measure the applied pressure, often converting it into an electrical signal for further processing.
Which device is used to measure the temperature of an object?
A Thermometer
B Thermocouple
C Strain gauge
D Pressure gauge
Thermocouples measure temperature by generating a voltage based on the temperature difference between two different materials.
What is the purpose of a signal conditioner?
A To measure displacement
B To amplify and filter raw signals
C To store signals
D To transmit signals wirelessly
Signal conditioners prepare raw signals from sensors or transducers by amplifying, filtering, and converting them into usable formats.
What is the primary purpose of a dynamometer-type wattmeter?
A To measure average power in AC and DC circuits
B To measure instantaneous voltage
C To measure current
D To measure resistance
Dynamometer-type wattmeters measure average power in both AC and DC circuits by utilizing the interaction of magnetic fields.
What is the function of a potentiometer in electrical measurements?
A To compare unknown voltage with a reference
B To measure current
C To measure temperature
D To measure resistance
A potentiometer is used to compare an unknown voltage with a reference voltage for precise measurement of voltage.
What is the primary use of a Kelvin bridge?
A To measure low resistance accurately
B To measure capacitance
C To measure voltage
D To measure frequency
Kelvin bridges are designed to measure low resistances accurately by eliminating the effects of contact resistance and lead resistance.
What is the primary purpose of a current transformer (CT)?
A To step down current for measurement
B To step up voltage
C To step down voltage for measurement
D To measure resistance
Current transformers (CTs) step down high currents to lower, measurable levels, making them ideal for metering and protection.
Which instrument is used to measure small voltages accurately?
A Galvanometer
B Voltmeter
C Ammeter
D Wattmeter
Galvanometers are designed to detect and measure very small voltages or currents by utilizing the deflection of a needle within a magnetic field.
Which of these is a renewable energy source?
A Coal
B Solar energy
C Natural gas
D Diesel
Renewable energy sources can naturally replenish over time, such as sunlight, wind, and water. Solar energy is renewable, while coal, natural gas, and diesel are non-renewable fossil fuels.
What is the meaning of “photovoltaic”?
A Generating heat energy
B Converting sunlight into electricity
C Storing electricity
D Producing mechanical power
Photovoltaic (PV) technology converts sunlight directly into electrical energy using semiconductors like silicon in solar cells.
Which device is used to convert sunlight into electricity?
A Wind turbine
B Solar panel
C Battery
D Generator
Solar panels, composed of photovoltaic cells, capture sunlight and transform it into electricity. Wind turbines and generators are used for other energy systems.
What is the main component of a wind energy system?
A Solar collector
B Wind turbine
C Biomass plant
D Battery bank
A wind turbine is the key component that converts the kinetic energy of wind into mechanical energy, which is then transformed into electricity using a generator.
What is the energy source for hydropower plants?
A Wind
B Flowing water
C Sunlight
D Biomass
Hydropower plants generate electricity by harnessing the kinetic and potential energy of flowing or falling water to rotate turbines connected to generators.
Which of these is a key feature of renewable energy?
A Limited availability
B Naturally replenished
C High carbon emissions
D Requires fossil fuels
Renewable energy is derived from resources that replenish naturally over time, like sunlight, wind, and water, making it sustainable and low-emission compared to fossil fuels.
What does a “feed-in tariff” policy promote?
A Reducing energy consumption
B Encouraging renewable energy production
C Building more fossil fuel plants
D Lowering electricity prices
Feed-in tariffs are government policies offering fixed payments to renewable energy producers for feeding electricity into the grid, incentivizing clean energy adoption.
Which type of renewable energy system uses geothermal energy?
A Solar panel system
B Ground source heat pumps
C Wind turbine system
D Hydropower system
Geothermal energy utilizes heat from beneath the Earth’s surface. Ground source heat pumps transfer this thermal energy for heating and cooling applications.
What is “biomass energy”?
A Energy from flowing water
B Energy from organic materials
C Energy from wind turbines
D Energy stored in batteries
Biomass energy is derived from organic materials like wood, agricultural residues, and animal waste. It is considered renewable when sourced sustainably.
What does “net metering” allow in renewable energy systems?
A Selling excess electricity back to the grid
B Reducing power plant emissions
C Storing unused energy in batteries
D Reducing electricity usage
Net metering allows renewable energy system owners to send surplus electricity back to the grid and receive credit, reducing their overall utility bills.
Which renewable energy source has the highest efficiency for converting energy into electricity?
A Wind energy
B Solar energy
C Geothermal energy
D Biomass energy
Geothermal power plants typically have high conversion efficiency (10-20%) due to the consistent availability of heat from the Earth, unlike variable sources like wind and solar.
What is the purpose of an inverter in a solar energy system?
A Convert direct current (DC) to alternating current (AC)
B Store solar energy
C Increase the sunlight intensity
D Connect solar panels to the grid
Solar panels generate DC electricity, which must be converted to AC by an inverter to be compatible with home appliances and the power grid.
Which of these is a hybrid renewable energy system?
A Solar-only system
B Wind-only system
C Solar and wind system
D Fossil fuel generator
Hybrid renewable systems combine two or more energy sources, such as solar and wind, to improve reliability and energy generation under varying conditions.
What is the main environmental benefit of renewable energy?
A High energy efficiency
B Reduced carbon emissions
C Low installation cost
D Consistent power supply
Renewable energy systems produce minimal greenhouse gas emissions compared to fossil fuels, making them environmentally friendly and crucial for combating climate change.
Which energy storage method is commonly used in off-grid systems?
A Pumped storage
B Battery storage
C Thermal storage
D Flywheel storage
Batteries are commonly used in off-grid renewable systems to store excess energy generated during peak production for later use when generation is low.
What is a “smart grid”?
A A power grid using artificial intelligence
B A grid designed for renewable energy integration
C A grid with backup generators
D A grid with low voltage
A smart grid incorporates digital technology to monitor, manage, and efficiently integrate renewable energy sources, improving reliability and sustainability.
What is the primary energy source for tidal power?
A Ocean waves
B Gravitational pull of the moon
C Sunlight
D Heat from the Earth
Tidal energy harnesses the movement of water caused by the gravitational forces of the moon and sun on Earth’s oceans.
Which country is a global leader in wind energy production?
A India
B Germany
C United States
D China
China leads the world in wind energy capacity and production due to significant investments in wind turbine installations and renewable energy policies.
What does “carbon footprint” measure?
A Total energy consumption
B Greenhouse gas emissions
C Power generation capacity
D Energy storage capacity
Carbon footprint refers to the total greenhouse gases emitted directly or indirectly by an individual, organization, or activity, measured in CO₂ equivalents.
What is an energy audit?
A A test of energy storage systems
B An analysis of energy usage patterns
C A review of power grid failures
D A method of generating renewable energy
An energy audit identifies how energy is consumed and highlights opportunities to improve energy efficiency and reduce waste.
What is the primary energy conversion in a solar thermal system?
A Light to electricity
B Heat to mechanical energy
C Sunlight to heat energy
D Chemical energy to electrical energy
Solar thermal systems collect sunlight and convert it into heat energy, which is then used for applications like water heating or powering turbines for electricity generation.
What type of energy is harnessed by wave energy converters?
A Kinetic energy of water
B Gravitational pull of the moon
C Chemical energy in ocean water
D Solar radiation
Wave energy converters capture the kinetic energy from the motion of ocean waves and convert it into usable electricity.
Which of these is NOT a renewable energy source?
A Geothermal energy
B Natural gas
C Wind energy
D Biomass energy
Natural gas is a fossil fuel and not a renewable resource, unlike geothermal, wind, and biomass energy, which are naturally replenished.
What is the purpose of a charge controller in a solar energy system?
A To convert DC to AC
B To regulate battery charging and prevent overcharging
C To measure solar panel efficiency
D To track the sun’s position
A charge controller ensures the batteries in a solar system are charged efficiently and safely, protecting them from overcharging or deep discharge.
What is the term for energy generated from organic materials like wood, agricultural waste, and animal manure?
A Solar energy
B Biomass energy
C Tidal energy
D Geothermal energy
Biomass energy is derived from organic materials. It can be burned for heat or converted into biofuels like ethanol and biodiesel.
Which component of a wind turbine captures the wind’s kinetic energy?
A Rotor blades
B Generator
C Tower
D Inverter
Rotor blades capture the kinetic energy of the wind and cause the turbine to rotate, which generates mechanical energy converted into electricity.
What is the role of a battery management system (BMS)?
A To generate electricity
B To ensure optimal performance and safety of batteries
C To convert DC to AC power
D To connect renewable systems to the grid
A BMS monitors battery voltage, temperature, and state of charge, ensuring safety, longevity, and efficiency in energy storage systems.
What is the main cause of variability in solar and wind energy?
A Mechanical failure
B Weather conditions
C Inefficient technology
D Grid design
Solar and wind energy are intermittent because their availability depends on factors like sunlight, cloud cover, wind speed, and weather patterns.
What is an off-grid renewable energy system?
A A system connected to the main power grid
B A system without any storage
C A system that operates independently of the main grid
D A system used only for heating
Off-grid systems generate and store their own energy, providing electricity without relying on a central power grid. They are common in remote areas.
What is a microgrid?
A A large-scale grid that powers cities
B A localized grid that can operate independently
C A storage system for renewable energy
D A grid used only for wind energy
A microgrid is a smaller, localized version of the traditional grid, designed to integrate renewable energy and operate independently during outages.