If 5.0 x 10^21 electrons pass through a 20-Ω resistor in 10 min, what is the potential difference across the resistor?

26.67 Volt

Explanation:

number of electrons, n = 5 x 10^21

R = 20 ohm

t = 10 min = 10 x 60 = 600 sec

V = ?

q = n x charge of one electron

q = n x e

q = 5 x 10^21 x 1.6 x 10^-19 = 800 C

i = q / t = 800 / 600 = 4 / 3 A

According to Ohm's law

V = i x R

V = 4 x 20 / 3 = 26.67 Volt