Tag: the essence of change

Questions Related to the essence of change

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

  1. mechanical, electrical

  2. mechanical, chemical

  3. potential, electrical

  4. electrical, chemical


Correct Option: A
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.

A motor converts:

  1. electrical energy into mechanical energy

  2. mechanical energy into electrical energy

  3. electrical energy into heat energy

  4. heat energy into electrical energy


Correct Option: A
Explanation:

A motor converts electrical energy into mechanical energy.

In which of the following chemical energy is converted into heat energy?

  1. Heater

  2. Cooler

  3. Motor

  4. Candle


Correct Option: D

During photosynthesis, green plants convert:

  1. chemical energy into light energy

  2. light energy into chemical energy

  3. light energy into mechanical energy

  4. light energy into muscular energy


Correct Option: B
Explanation:

During photosynthesis, green plants convert light energy into chemical energy stored in the form of food.

Which of the following devices convert light energy into electrical energy?

  1. An electric bulb

  2. A photocell

  3. A microphone

  4. A dynamo


Correct Option: B
Explanation:

A photocell gives out electric current when light is incident on it. So, it converts light energy into electrical energy.

Which of the following devices does not convert electrical energy into sound energy?

  1. A loud speaker

  2. A microphone

  3. A buzzer

  4. An electric bell


Correct Option: B
Explanation:

A microphone converts sound energy into electrical energy. All other devices mentioned convert electrical energy into sound energy.

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


Correct Option: D
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.

A running car converts:

  1. chemical energy into mechanical energy

  2. mechanical energy into chemical energy

  3. potential energy into kinetic energy

  4. no energy


Correct Option: A
Explanation:

A running car burns fuel and thus moves. So, it converts chemical energy into mechanical energy.

By charging a battery, we convert electrical energy into

  1. heat energy

  2. chemical energy

  3. magnetic energy

  4. mechanical energy


Correct Option: B
Explanation:

By charging a battery, we convert electrical energy into chemical energy. A battery, on the contrary, in use, converts chemical energy into electrical energy.

A loud speaker converts:

  1. electrical energy into sound energy

  2. sound energy into electrical energy

  3. mechanical energy into sound energy

  4. sound energy into mechanical energy


Correct Option: A
Explanation:

A loud speaker converts electrical energy into sound energy.