Answer:
Chemical energy to electrical energy to mechanical and thermal energy
Explanation:
In the rotating fan, the chemical energy stored in the battery is used to generate electrical energy.
The electrolytes within the battery undergoes chemical reactions that produces electric current.
- The current is being used to drive the motor of the fan to produce a mechanical energy as it rotates.
- In like manner, heat energy is also produced.
- So, energy is simply being transformed from one form to the other in this system.
Answer:
73 db
Explanation:
A single air conditioner is equivalent to 70 dB frequency. An extra air conditioning unit would therefore double the sound frequency. It does not, however, double the decibels to 140 dB. Instead, it adds only 3 dB to the 70 dB, making the total decibels of two air conditioning units equal to 73 db
Hence the correct option is b that is 73 db