Question

When a body is rubbed with another body a certain number of electrons are transferred. If the same number of electrons are allowed to flow through the cross-section of a conductor in $2s$, $10A$ electric current can flow through it. Determine the number of electrons transferred.

• A. $215\times {10}^{18}$
• B. $16\times {10}^{18}$
• C. $675\times {10}^{18}$
• D. $125\times {10}^{18}$

Answer 1

Answer: (D)

$125\times {10}^{18}$

Current flowing through the conductor, $I=10A$

Time, $t=2s$

According to quantization of charge,

Total charge,$Q=Ne$ (where, $N=$ number of electrons, $e=$ charge of an electron $=1.6\times {10}^{-19}C$)

We know,

$I=\frac{Q}{t}=\frac{Ne}{t}$

$⟹N=\frac{It}{e}$

$⟹N=\frac{10\times 2}{1.6\times {10}^{-19}}$

$⟹N=125\times {10}^{18}$