Sanskrit Word for Bell is Ghanta/GhantiThe Sanskrit word for bell is Ghanta/Ghanti which is mainly used at time of poojas for call or invoking the Gods. When we ring the bell it is supposed to produce an auspicious sound "Om", which is nothing but the universal name of the Lord.Aarthi is also accompanied most of the time by ringing of the bell, sounds of conches and other musical instruments. The ringing of the bell with other accompanied instruments is mainly to help the devotees pray in full concentration and peace so that they pay no heed to other insignificant sounds and disturbances from the surroundings.
There are no Temples which can be seen without a Bell-There are no temples which can be seen without a bell and usually a large bell is hung at the entrance of the temple so that it is a custom to ring the bell and then enter. The reason behind ringing the bell and then entering is that as the sound is produced by the bell our brain automatically is emptied of all thoughts and we enter into a trans- state of mind where the bell works as an anti-dote. Giving a sudden shock is the only way to wake up our brain and prepare ourselves or taste of awareness and this is done by the ringing of the bell. There are also other reasons behind the ringing of the bell, in ancient days temples were mostly situated near hills and forest and there used to be all possibilities of wild animals or other living creatures like insects and birds which might have its shelter there. So bell sound never let any wild animals or other creatures to be in for a prolonged time.
The Scientific Phenomenon Behind the BellThe scientific phenomenon behind the bell is that it is constituted or made of different kinds of metals like cadmium, lead, copper, zinc, nickel, chromium and manganese and each of these metals is mixed at the right proportion. This gives a unique sound so that it unites both the left and the right brain. Once the bell is rung, it produces a very sharp and a long lasting sound which goes about for at least a minimum of seven seconds like an echo which penetrates the seven healing points or the chakras in our body. There also beliefs among the Hindus that the ringing of the bell brings positive vibrations leading to magnification of the spiritual experience of the devotee. The daily ritualistic pooja in most of the Hindu temple is accompanied by the ringing of the bell and the following chanting of the mantra which means "I ring this bell indicating the invocation of divinity, So that virtuous and noble forces enter (my home and heart); and the demonic and evil forces from within and without, depart."
"Aagamaarthamtu devaanaam gamanaarthamtu rakshasaam Kurve ghantaaravam tatra devataahvaahna lakshanam"