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

Which of the following is the underlying principle of the steam engine?

  1. Transformation of heat into mechanical energy

  2. Transformation of heat into electric energy

  3. Transformation of electric energy into heat

  4. Transformation of mechanical energy into heat
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

James watt framed the idea that heat energy can be transformed into other forms of energy. The heat energy can also be generated from other various form of energy. Keeping these ideas in his mind, he used the chemical energy of fuel, like coal, to produce steam to rotate the shaft of the engine. In other words, we can say that the heat energy is converted into mechanical energy.

Multiple choice

Which one of the following is not matched correctly?

  1. Steam engine : Heat energy to mechanical energy

  2. Geyser : Electrical energy to mechanical energy

  3. Nuclear power plant : Nuclear energy to electrical energy

  4. Burning of candle: Chemical energy to heat energy

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In geyser, electrical energy is converted into heat energy. This option is incorrectly matched. 

Multiple choice

Human body is an example of

  1. isolated system

  2. closed system

  3. open system

  4. adiabatic system
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This system involves the exchange of both matter and energy with the surroundings. Since human body exchanges both matter and energy with the surroundings, it is an open system.

Multiple choice

Which of the following energy conversions occur inside a battery?

  1. Electrical to Chemical

  2. Thermal to Electrical

  3. Thermal to Chemical

  4. Chemical to Electrical

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The chemical reactions cause the negative terminal to become negatively charged and the positive terminal to become positively charged. The negative and positive charges on the battery terminals produce the electric field in the circuit that causes electrons to flow.

Multiple choice

The switching off of unnecessary lights and fans is an example of

  1. reduction

  2. recycling

  3. reusing

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

Reducing the amount of waste produced is the best way to help the environment. For example, cars use up energy and cause pollution. Some ways to reduce the environmental damage caused by cars include carpooling with friends, walking, taking the bus or riding a bicycle.

Multiple choice

Match the following:

 
Example Conversion of energy
1. Electric bulb A. Chemical energy to electrical energy
2. Door bell B. Electrical energy to light energy
3. Dry cell C. Electrical energy to heat energy
4. Electric iron D. Electrical energy to sound energy

  1. 1 - B, 2 - C, 3 - A, 4 - D

  2. 1 - B, 2 - D, 3 - C, 4 - A

  3. 1 - B, 2 - D, 3 - A, 4 - C

  4. 1 - C, 2 - D, 3 - B, 4 - A

  5. 1 - C, 2 - D, 3 - A, 4 - B
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is the right answer. Electric bulb converts electrical energy to light energy. Door bell converts electrical energy to sound energy. Dry cell converts chemical energy to electrical energy and electric iron converts electrical energy to heat energy.

Multiple choice

What does OTEC stand for?

  1. Ocean Temperature Energy Conversion

  2. Ocean Thermal Energy Conversion

  3. Ocean Tidal Energy Conversion

  4. Ocean Temperature Energy Collection
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

OTEC stands for Ocean Thermal Energy Conversion.

Multiple choice

What type of energy transformation takes place in thermal power plants?

  1. Electrical energy is converted into mechanical energy.

  2. Heat energy is converted into chemical energy.

  3. Heat energy is converted into electrical energy.

  4. Electrical energy is converted into chemical energy.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Heat energy is converted into electrical energy because when fuel burns, heat energy is produced, which is converted into electrical energy.