In some fairly recent experiments physicists have claimed to able to stop light entirely in super-cooled sodium.
Gases
Light can travel through vacuum, but it is not a medium.
Light can travel with and without a medium.
Within the same medium, all electromagnetic waves travel at the same speed.
it is sound that requires a medium to travel .. light is an electromagnetic wave ..it doesn't require a medium..
Gases
metal,wood and then brick. yes all the basics
Sound waves don't just travel the slowest in a vacuum, they don't travel at all. The reason is that sound waves, like all mechanical waves, need a medium to travel through.
No, light is at its fastest in a vacuum.
Light can travel with and without a medium.
Light can travel through vacuum, but it is not a medium.
Within the same medium, all electromagnetic waves travel at the same speed.
it is sound that requires a medium to travel .. light is an electromagnetic wave ..it doesn't require a medium..
Light will not travel into silver.
No, it does not. It can travel through any open space. Sound, unlike light, needs a medium to travel. So light can travel through outer space but sound cannot because there is no medium.
how can we say light does not need light to travel
No, light in a medium will travel at a slower speed.