The axoplasm of an axon has a resistance Rax. The axon's membrane has both a resistance (Rmem) and a capacitance (Cmem). A single segment of an axon can be modeled by a circuit with Rmem and Cmem in parallel with each other and in series with an open switch, a battery, and Rax?.

Imagine the voltage of the battery is ?V?.

Imagine that after a very long time there is a current I going through the battery. The potential difference across the membrane can be written as I Rmem.

Write down another expression for the potential difference across the membrane using all or some of the given variables, except Rmem.