Question

A battery of emf 2 V and internal resistance $0.5\Omega$ is connected across a resistance of $9.5\Omega$. How many electrons cross through a cross section of the resistance in 1 second ?

Answer 1

Current, $I=\frac{V}{R_{total}}=\frac{2}{0.5+9.5}=0.2A=0.2C{s}^{-1}$

Number of electron $=\frac{Q_{total}}{1.6\times {10}^{-19}}=\frac{It}{1.6\times {10}^{-19}}=\frac{0.2\times 1}{1.6\times {10}^{-19}}$

Number of electron$=1.25\times {10}^{18}nos.$