A device in which an electromagnetically operated hammer strikes a bell (see illustration). Pressing the bell-push closes a circuit, causing current to flow from a battery or mains step-down transformer through an electromagnet. The electromagnet attracts a piece of soft iron attached to the hammer, which strikes the bell and at the same time breaks the circuit. The hammer springs back into its original position again, closing the circuit and causing the magnet to attract the soft iron. This process continues until the bell-push is released.
Electric bell
- luminosity
- luminous exitance
- luminous flux
- luminous intensity
- lunar eclipse
- lunation
- lux
- Lyman series
- m.k.s. units
- m.m.f.
- Mach number
- Mach's principle
- machine
- Maclaurin's series
- macroscopic
- Magellanic clouds
- magic numbers
- Magnadur
- Magnalium
- magnet
- magnetic bottle
- magnetic bubble memory
- magnetic circuit
- magnetic compass
- magnetic constant