How glass is broken with sound?

When any object composed of an elastic material is disturbed, it will vibrate at its own special set of frequencies, which together form its special sound.The frequency is the natural frequency of that object. The tendency of one object to force another object into vibrational motion is called forced vibration. If an unmounted tuning fork is struck, the sound it makes is faint. Hold the base of the fork on a table top, and the sound is relatively loud. This is because the table is forced to vibrate, and its larger surface sets more air in motion. The table top becomes a sounding board, and can be forced into vibration with forks of various frequencies. When the frequency of forced vibrations on an object matches the object's natural frequency, a dramatic increase in amplitude occurs. This phenomenon is known as resonance. A glass has a natural frequency. Now if the pitch of the sound creating forced vibration match the resonant frequency of glass the vibrating air will cause the glass vibrating too. If this occur with sufficient volume, right frequency and high enough amplitude, this will cause exceed the strength of the glass to resist the vibrations. When the sound gets too loud for the glass to vibrate, it breaks the glass.  

Glass

How can we see through glass?

SCIENCE FACTS(Glass)

Glass is a transperant object which is an amorphous(non-crystalline) solid. The primary constituent of glass is sand(silicon dioxide,SiO₂).The atoms in a solid are tightly bound to each other.The molecules are held together with strong intermoleculer force.Therefore the molecules can not move freely and the space between them is very little.So,they do not allow light to pass through them.Light can pass through liquids and gases because the molecules of liquids and gases can move freely and a lot of space between them.Glass is manufactured by melting sand at a very high temperature and then cooling it.Therefore brittle substance is produced but glass still contains the free moving molecules of a liquid.So,light can pass through the free space between the molecules although glass itself is a solid.