Question

Gibe reason bells re made of metals

Answer 1

Since metal are sonorous (produce sound on vibrating) they are used to make bells

Answer 2

we know that metals are sonorous i.e.produce a ringing sound when hit.
when the bell rings the sound is produced due to this property
in the case of non metals as they are not sonorous they are not used for making bells
hope it helps
#aditya