School bells are made of metals because metals are

School bells are made of metals primarily because of their sonorous nature. Sonority is the physical property of metals that enables them to produce a deep, ringing sound when struck by a hard object [1]. While metals also possess other properties such as malleability (the ability to be beaten into thin sheets) [4], ductility (the ability to be drawn into wires) [3], and lustre (a shiny appearance) [2], these characteristics do not contribute to the sound-producing capability required for a bell. Non-metals like wood or coal produce dull sounds, whereas metals allow for the clear, resonant vibrations necessary for acoustic signaling [2]. Therefore, the specific property utilized for making bells, wind chimes, and musical instrument strings is sonority [2].

Sources

1. [1] Science-Class VII . NCERT(Revised ed 2025) > Chapter 4: The World of Metals and Non-metals > Activity 4.2: Let us investigate > p. 46
2. [4] Science-Class VII . NCERT(Revised ed 2025) > Chapter 4: The World of Metals and Non-metals > Table 4.1: Appearance, hardness, and eff ect of hammering on diff erent objects or materials > p. 43
3. [3] Science-Class VII . NCERT(Revised ed 2025) > Chapter 4: The World of Metals and Non-metals > 4.1.2 Ductility > p. 44
4. [2] Science , class X (NCERT 2025 ed.) > Chapter 3: Metals and Non-metals > What you have learnt > p. 55