MHT CET · Physics · Electrostatics
When a piece of polythene is rubbed with wool, a negative charge of \(4 \times 10^{-7} \mathrm{C}\) is developed on the polythene. The number of electrons transferred wool to polythene is \(\left[\mathrm{e}=1.6 \times 10^{-19} \mathrm{C}\right]\)
- A \(1.5 \times 10^{12}\)
- B \(3.5 \times 10^{13}\)
- C \(2.5 \times 10^{13}\)
- D \(2.5 \times 10^{12}\)
Answer & Solution
Correct Answer
(D) \(2.5 \times 10^{12}\)
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & \mathrm{q}=4 \times 10^{-7} \\ & \mathrm{q}=\mathrm{Ne} \\ & \mathrm{N}=\frac{\mathrm{q}}{\mathrm{e}}=\frac{4 \times 10^{-7}}{1.6 \times 10^{-19}}=2.5 \times 10^{12}\end{aligned}\)
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