Sound requires vacuum, vibration and a medium, only air, or light waves?
آواز کے لیے خلا، ارتعاش و واسطہ، صرف ہوا یا روشنی چاہیے؟
Solution & explanation
A vibrating source and a material medium. Sound can travel in solids and liquids as well as gases.
Independent study answer. Original textbook ↗ · English-medium printed page 60.