Science General ยท Physics
Energy and Electrical Devices
1,182 Questions
Energy and electrical devices focus on energy conversion, household electrical appliances, batteries, and electric vehicle technology. These principles are essential components of general science syllabi across major competitive examinations. Review these practice questions to strengthen understanding of electrical energy applications and devices.
Energy conversionHousehold electrical appliancesBatteries and cellsElectric vehicles
Energy and Electrical Devices Questions
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mechanical energy
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electrical energy
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thermal energy
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none of these
B
Correct answer
Explanation
A battery converts chemical energy into electric energy.
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Otto cycle
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Joule cycle
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Rankine cycle
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Stirling cycle
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suction, expansion, compression and exhaust
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suction, compression, expansion and exhaust
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expansion, compression, suction and exhaust
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compression, expansion, suction and exhaust
B
Correct answer
Explanation
The correct option is option 2.
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theoretical power
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actual power
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indicated power
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mechanical power
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in the engine cylinder
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at the crank shaft
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at the crank pin
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None of these
B
Correct answer
Explanation
The break power is the power available at the crank shaft.
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Mixer grinder
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Air conditioner
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Gas burner
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Television
C
Correct answer
Explanation
A gas burner does not require electricity. It uses LPG to burn.
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Switch
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Terminal
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Conductor
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Motor
A
Correct answer
Explanation
A switch when open prevents the flow of current and when closed allows the current to flow.
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Battery
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Dynamo
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Washing Machine
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Battery charger
C
Correct answer
Explanation
A washing machine uses an electric motor to convert electrical energy into mechanical energy to rotate the drum.
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Battery
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Dynamo
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Washing Machine
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Battery charger
D
Correct answer
Explanation
A battery charger takes electrical energy from an external source and converts it into chemical energy stored within a battery. A battery itself acts as a source of chemical energy, while a dynamo converts mechanical energy to electrical energy.
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Battery
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Dynamo
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Washing Machine
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Battery charger
A
Correct answer
Explanation
A battery stores energy in chemical form and releases it as electrical energy during discharge. This is the reverse process of a battery charger.
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Battery
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Dynamo
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Washing Machine
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Battery charger
B
Correct answer
Explanation
A dynamo (or generator) uses electromagnetic induction to convert mechanical energy (rotation) into electrical energy. A battery does the opposite.
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Microphone
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An electric bell
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Radio
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Loud speaker
A
Correct answer
Explanation
A microphone is a transducer that converts sound waves (mechanical energy) into electrical signals. Loudspeakers perform the reverse, converting electrical energy into sound.
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Nickel-cadmium
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Alkaline
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Lithium ion
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Nickel metal hydride
B
Correct answer
Explanation
Alkaline batteries are primary cells, meaning they are designed to be used once and then discarded. Nickel-cadmium, Lithium-ion, and Nickel metal hydride are all secondary (rechargeable) battery chemistries.
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Transformer
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Motor
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Electrometer
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Barometer
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None of these
E
Correct answer
Explanation
An electric generator (or dynamo) is the instrument that converts mechanical energy into electrical energy. None of the listed options (Transformer, Motor, Electrometer, Barometer) perform this specific function.
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electrical energy is converted into chemical energy
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electrical energy is converted into heat energy
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electrical energy is converted into magnetic energy
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all of these
A
Correct answer
Explanation
Electroplating is an electrolytic process where electrical energy is used to drive a non-spontaneous chemical reaction, converting electrical energy into chemical energy.