Why does light travel through a vacumn but sound doesn’t?

Question: Why does light travel through a vacumn but sound doesn't?
- Keywords:
  light,
  sound,
  vacuum
Asked by ROYLE to Norah, James, Dominic on 15 Mar 2017.
- James Harpur answered on 15 Mar 2017:
  
  Sound traves through the air and is dependant on it. In a vacuum without it, it doesn’t travel. Light is electromagnetic radiation in the form of waves and does not need air.

Question: Why does light travel through a vacumn but sound doesn't?