Question

If 4.1 × 1021 electrons pass through a 40 Ω resistor in 5 min, what is the potential difference across the resistor? The fundamental charge is 1.602 × 10−19 C . Answer in units of V

Answer 1

Answer:

Potential difference across resistor will be 87.66 volt

Explanation:

We have given number of electrons $n=4.1\times 10^{21}$

Charge on one electron $e=1.6\times 10^{-19}C$

So total charge $Q=4.1\times 10^{21}\times 1.6\times 10^{-19}=656C$

Time is given t = 5 min

1 minute = 60 sec

So 5 minute = 5×60 = 300 sec

So current $i=\frac{Q}{t}=\frac{656}{300}=2.1866A$

Resistance is given R = 40 ohm

Sp from ohm's law potential difference across resistor v = iR = 2.1866×40 = 87.466 volt