School bell
device · 1850 · Industrial Revolution
An electric bell rung on a schedule.
What it is made of
- Electromagnet — has part. An electromagnet strikes the hammer.
- Bell clapper hammer — has part. It strikes the gong.
- Bell gong — has part. A metal cup resonator.
- Interrupter contact — has part. It breaks the circuit, making the armature vibrate.
Principles and materials it uses
- Brass — is made of. The bell’s gong is brass.
What it is a kind of
- Electric bell — is a kind of. An electric bell.