<u>Answer</u>:
Cell phones contain rechargeable batteries that transform chemical energy into electrical energy. When using your cell phone, electrical energy is first transformed into <u>Electromagnetic waves </u>that are transmitted through the air.
<u>Explanation</u>:
When chemical energy is converted into electrical energy in cell phones, then this electrical energy firstly transformed or converted into electromagnetic waves which travels through air. Then this electromagnetic wave is converted into sound energy due to which users are able to listen audio, music, movies etc on their mobile phones.
The electrochemical energy that stored in a cell is removed as electrical energy in the process of discharging. There are so many other thermal and electrochemical processes taking place at the same time.
C - why do we produce it?
Answer: c) participant observation.
Explanation:
Participant observation is the qualitative research mechanism through which researchers get involved in the research activity along with the participants for studying and observing.It gives comprehensive understanding to researcher.It is usually carried out in field of sociology and anthropology.
According to the question,John is using participant observation as he is becoming a part of research along with homeless people to keenly observe the process and collect data on basis of that.
Other options are incorrect because secondary data analyzation, comparative research and qualitative technique are not used by investigator to become a part of research along with participants.Thus,the correct option is option(c).
