About how fast does a nerve impulse travel along a cell membrane?

1. An action potential at one spot changes the permeability of the neighbouring membrane. 2. The neighbour then depolarizes in turn, and so the pulse steps along the membrane. 3. Because each step needs ions to move, the impulse travels slowly, about 1 m/s. 4. That is nothing like the 10^8 m/s at which an electrical signal moves in a metal wire. 5. It is also far faster than the 10^-4 m/s drift velocity of electrons in a copper conductor. 6. So a nerve impulse sits between the two, which is why reaction times are measured in tenths of a second. _Source: OpenStax College Physics (CC BY 4.0), Ch 20 "Electric Current, Resistance, and Ohm's Law", section Nerve Conduction_