Instruction: View the "Transmission of Sound" video and Take the Quiz
Source: Youtube:Designmate Pvt. Ltd. - Official
Instruction: The video provides unique experiments on creating a speaker phone. You are challenged to choose one of the experiments and create your own.
Source: Youtube: DIY Crafts
Source: Youtube:Hack Guru
How to make mobile speakers from soda can without using any electronics?
mobile speakers from soda cans (pepsi vs coca cola).
Source: Youtube:Marco’s HAX