hat does this mean - nonmetals are not sonorous?

 non metals do nat make sound when  hit against a hard object.so they are not sonoros

 hiii... !!! well it jst means dat.. non metals do not produce sound... dats y dey r not sonorous... while metals r sonorous bcoz dey make sound.. 

Non metals are sonorous.. This means that even when hit against a hard surface, non-metals do not make any sound, unlike metals. Hence, metals are said to be sonorous because they make a ringing sound when hit against a hard surface. But do keep in mind some exceptions!

Hope this satisfies your question. 

 Hi, its true that metals produse sound and are sonorous whereas non metals do not produce sound. For eg:-

Take a metal say iron. hit it hard with a hammer. What do u observe? U will observe that it produces a ringing sound. Try doing the same with a non metal. What happens? No RINGING sound is produced. Therefore this proves my answer.