Answer: 23.56 nV
Explanation:
Assuming that we apply Ohm's Law to this situation, we know that under this condition, the current resultant, is proportional to the voltage applied, and that the proportionality constant, is called the resistance.
Now, we define electric current, as the passage of a number of charges over time.
In this case, we can say that each singly-ionized potassium ion carries the charge equivalent to the one electron, which is q = 1.6. 10⁻¹⁹ coulombs.
So, as we have 90,000 ions, we will have a total charge as follows:
Q =90.10³. 1.6.10⁻¹⁹ coulombs
Also, we are told that this charge will be moving for 1.1 msec, so we can find the current I as follows:
I = Q/t ⇒ I = 13.09. 10⁻¹² A.
If we know that R= 1.8.10⁹ Ω, we can determine V, applying Ohm's Law, as follows:
V = 13.09. 10⁻¹² A . 1.8.10⁹ Ω = 23.56 nV
