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 physics the essence of change different forms of energy energy conversions energy transformations and energy transfers

The device / machine which converts chemical energy into electrical energy is

  1. Electric bulb

  2. Electric motor

  3. Battery

  4. Solar cell
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Option A: Electrical bulb converts electrical energy into heat.

Option B: electrical motor converts electrical energy in mechanical energy.
Option C : battery converts chemical emergy into electrical energy.
Option D: solar cell converts light (using photons) into electrical energy.
So best possible answer is option C.

Multiple choice physics the essence of change different forms of energy energy conversions energy transformations and energy transfers

A generator is an arrangement which converts _________ energy into _________ energy.

  1. mechanical, electrical

  2. mechanical, chemical

  3. potential, electrical

  4. electrical, chemical
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 A generator converts mechanical energy into electrical energy.  Generator works due to this because of electromagnetic induction generated due to this conversion of energy. Also magnetic field is produced which results in generation of voltage that helps the generator to function.

Multiple choice physics the essence of change different forms of energy energy conversions energy transformations and energy transfers

A battery, left idle (i.e., not in use):

  1. converts chemical energy into electrical energy

  2. converts electrical energy into chemical energy

  3. converts electrical energy into light energy

  4. does no energy conversions
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When a battery is not in use, it does not give out electric current. So, the chemical energy stored in it does not get converted.

Multiple choice physics the essence of change different forms of energy energy conversions energy transformations and energy transfers

In the moving parts of a machine:

  1. heat energy gets transformed into mechanical energy

  2. kinetic energy gets transformed into potential energy

  3. mechanical energy gets transformed into heat energy

  4. no energy transformation takes place
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The moving parts of a machine get heated due to friction, thus changing a part of mechanical energy into heat energy.

Multiple choice physics the essence of change different forms of energy energy conversions energy transformations and energy transfers

Which of the following energy conversions take place in a torch?

  1. electrical $\rightarrow$ chemical $\rightarrow$ light
  2. chemical $\rightarrow$ electrical $\rightarrow$ light
  3. electrical $\rightarrow$ light $\rightarrow$ chemical
  4. light $\rightarrow$ chemical $\rightarrow$ electrical
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The chemicalenergy stored in batteries gets transformed into electrical energy through the wires. This then gets transformed into light energy that you see.