A polythene piece rubbed with wool is found to have a negative charge of $8 × 10^{-10}C$. What is the number of electrons transferred?

$5×10^9$; wool to polythene

$ q = ne $

Number of electron transferred is $ n = \frac{q}{e} = \frac{8\times 10^{-10}}{1.6\times 10^{-19}} = 5\times 10^9$

The correct answer is Option (3) → $5×10^9$; wool to polythene