# Telegraphic equation

From Glossary of Meteorology

## telegraphic equation

(Also called telegrapher's equation.) A partial differential equation usually written in the form where

*t*is a time coordinate,*x*is a space coordinate, and*a*and*b*are positive constants.This is the equation governing the flow of electricity in a cable. When

*b*< 0, the equation applies to the motion of long gravitational waves in a rotating ocean.