Science General · 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

Multiple choice

What energy transformation occurs within an electric motor?

  1. mechanical to electric

  2. chemical to electric

  3. electric to mechanical

  4. chemical to mechanical
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

An electric motor uses electrical energy to create rotational movement, which is mechanical energy. This is the inverse of a generator, which converts mechanical energy into electrical energy.

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

A cell in which chemical energy is converted into electric energy by first passing a current through it is called a _________.

  1. Primary cell

  2. Secondary cell

  3. Photocell

  4. Electrostatic machine
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The cell in which chemical energy is converted into electrical energy is called a primary cell. Leclanche cell, Daniel cell, Voltaic cell are all primary cells and not the storage cells.

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

In torch light cell is used as source of which energy ?

  1. Electrical Energy

  2. Mechanical Energy

  3. Chemical Energy

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In torch light, cell is used as a source of electrical energy.

As electrical cell internally converts stored chemical energy into electrical energy, allowing a current to flow from the positive terminal round to the negative one via an external circuit .

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

Which of the following is the purpose of an electrical cell?

  1. To change mechanical energy to electrical energy

  2. To change chemical energy to electrical energy

  3. To change electrical energy to mechanical energy

  4. To change electrical energy to chemical energy
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An electrical cell is an "electrical power supply" - internally it converts stored chemical energy into electrical potential energy, allowing a current to flow from the positive terminal round to the negative one via an external circuit (this is called conventional current, which is chosen to go from + to -).

Multiple choice physics sources of energy wave energy tidal energy wave power and tidal power

Full form of OCTEC is:

  1. Ocean Thermal Energy Conversion Power Plant.

  2. Ocean Thermal Consumer Energy Power Plant.

  3. Ocean Current Thermal Energy Cycle.

  4. Ocean Current Thermal Electric Plant.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

OCTEC stands for ocean thermal energy conversion power plant. It is a device used to harness tidal energy to produce electricity.

Multiple choice physics sources of energy wave energy tidal energy wave power and tidal power

Arrange the following steps of conversion of ocean thermal energy into electricity, in a proper sequence.
(a) The vapour of ammonia or CFC is passed over the turbines of generators.
(b) The hot water from the ocean is used to vapourise the liquid like ammonia or CFC.
(c) Cold water from the ocean depths is used to cool the vapour again into liquid.
(d) This cold liquid is again vapourised and the process continues.

  1. b a c d

  2. c a b d

  3. c b a d

  4. a b c d
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The hot water in the ocean is used to evaporate liquids like ammonia or CFC. This vapour is used to rotate the turbines of the generator and the vapour is again cooled down to a liquid by using the cold water from the ocean depth. This cooled liquid ammonia or CFC is again vapourised and the above process continues.

Multiple choice physics alternating currents sinusoidal current types of current movement of charge

Choose the correct statements from the following $A.C.$ cannot be used in

  1. Electroplating

  2. Charging a battery

  3. Charging a capacitor

  4. Electrolysis

  5. Heating a room
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Electroplating and electrolysis require a constant unidirectional current (DC) to ensure metal ions are deposited consistently on the cathode. AC would cause the ions to oscillate back and forth, preventing successful plating.

Multiple choice physics household circuits electric switch switch electrical circuit

A device that is used to break or make an electric circuit is called _________.

  1. potentiometer

  2. switch

  3. breaker

  4. fuse
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A 'switch' is an electric device that is used to make or break a circuit. When the switch is in 'OFF' position, then the circuit is not complete. Then, the circuit is called an Open circuit. An electric current cannot flow through the circuit. and vice versa.