Answers

2015-06-13T08:57:46+05:30
 Light and sound do not have mass. Light is electromagnetic wave transverse in nature while sound is longitudinal wave but since it requires a material medium to travel it is a mechanical wave. 
Moreover matter is the one which occupies the space. But waves do not occupy space. Electromagnetic waves don't need material medium, but sound waves do need a material medium to travel. Hence light and sound aren't considered as matter.
0
2015-06-13T09:47:19+05:30
 light and sound do not have mass. Light is electromagnetic wave transverse in nature. Sound is longitudinal wave. But sound needs material medium so it is mechanical wave. 
Moreover matter is the one which occupies the space. But waves do not occupy but traverse in space. Electromagnetic waves don't need material medium, but sound waves do need a material medium. 
False physics to assume that light has no mass. Energy = mc^2 =hf=cp. Light has energy and momentum. p=h/w =mv.
0