While regular glass would let around 91% of the light get through, the remaining 8% still is reflected back. The outer coating on anti reflective glass, on the other hand, lets only up to 2% of light to get away, making for a clearer view of what is on the other side....
Sound is measured in decibels (dB). For the human ear, it is possible to perceive changes in sound as low as 1 dB. To put this into context, a human whisper generally weighs in at 20 on the dB-based scale, while normal conversation stands at around 60 dB. And too long...
