why are bells made of metals?

 First, metal will make bells that will vibrate at a frequency and amplitude that can be heard without an excessive amount of applied energy. They will also sustain this oscillation for a suitable period of time. IOW, metal bells sound like bells. You could make a bell from wood, but it would make a clop-clop sound.

bells are made of metals because bells are made to produce a ringing sound and this ringing sound can be produced only by metals. this property of metal of producing a ringing sound on striking is called sonorous.

metels are sonorous in nature and this property of a metel helps a bell to produce sound when striked.

There are a few reasons why bells are made of metals.

First, metal will make bells that will vibrate at a frequency and amplitude that can be heard without an excessive amount of applied energy. They will also sustain this oscillation for a suitable period of time. IOW, metal bells sound like bells. You could make a bell from wood, but it would make a clop-clop sound.

Second, metal is strong enough to be repeatedly played without damage. You can make glass bells, and they work. If you have some wine glasses at home, hold one upside down and tap it with your fingernail. It sounds great. But if you were to play the glass with a metal object like a spoon, you'd break it into pieces.

Third, a metal bell is lighter than, say, a ceramic bell. They make ceramic bells, and they work fine. But they're heavier than metal bells the same size.

Fourth, you can tune a metal bell. If you make a ceramic bell and it doesn't sound quite right, you have to either make a new bell or learn to like the one you made. On a metal bell, if you think the mouth needs to be pinched in a little you pinch it in a little.

And fifth, metal bells are traditional...and in this case, tradition isn't bad.

Bells are made of metal because metal propagate more sound when struck, because of this you can clearly hear when the bell is struck. If it were wood then it would propagate less amount of sound and thus sometimes you coudn't have heard the sound produced by it.

this is  because metals are sonorus

 Bells are made of metals as the sound waves(vibrations) travel fastest in metals and because of this only we are able to hear sound more clearly. 

coz metal is sonorus