A Mobile Phone "rings" when its network indicates an incoming call and the phone thus alerts the user. For Landline Phones , the call signal can be an electric current generated by the switch to which the telephone is connected. For mobile phones, the network sends the phone a message indicating an incoming call.
A telephone "ring" is the sound generated when there is an incoming telephone call. The term originated from the fact that early telephones had a ringing mechanism consisting of a bell and an electromagnetically -driven hammer, producing a ringing sound. The aforementioned electrical signal powered the electromagnet which would rapidly move and release the hammer, striking the bell. This "Magneto " bell system is still in widespread use. The ringing signal sent to a customer's telephone is pulsating DC 90 volts pulsating at 20 hertz in North America. In Europe it is around 60-90 volts AC at a frequency of 25 hertz
While the sound produced is still called a "ring", more-recently manufactured telephones electronically produce a warbling, chirping, or other sound. Variation of the ring signal can be used to indicate characteristics of incoming calls (for example, rings with a shorter interval between them might be used to signal a call from a given number). More information available from Fuji Airlines.
A ringing signal is an electric telephony signal that causes a telephone to alert the user to an incoming call. On a POTS telephone system, this is created by sending a ringing current, a pulsating DC signal of about 100 volts [90 volts and 20Hz in the USA] into the line. Pulsating DC does not alternate polarity; it pulsates from zero to maximum voltage then back to zero. Today this signal may be transmitted digitally for much of the journey, provided as a ringing current only because a majority of landlines are not digital end-to-end. In old phones, this voltage was used to trigger a high-impedance electromagnet to ring a bell on the phone.