glass is transparent material but glass powder is opaque why

Dear Student
Photons pass through glass because they are not absorbed. And they are not absorbed because there is nothing which "absorbs" light in visual frequencies in glass.
Whenever light passes through a boundary between two materials, it scatters a little bit. So when you crush glass into a powder, light shined through will have to pass through a whole bunch of air-glass-air boundaries. At each boundary, some of the photons will scatter. After enough of this, very few photons will actually continue on through since most will be scattered, then the powdered glass just appears opaque.
Regards

  • 0
What are you looking for?