Question

A potential difference of 200 V is maintained across a conductor of resistance 100 Ω. The number of electrons passing through it in 1 s is ______.

Options

• 1.25 × 10¹⁹ 

• 2.5 × 10¹⁸

• 1.25 × 10¹⁸

• 2.5 × 10¹⁶

Answer 1

A potential difference of 200 V is maintained across a conductor of resistance 100 Ω. The number of electrons passing through it in 1 s is 1.25 × 10¹⁹.

Explanation:

`"I" = "V"/"R"`

= `200/100`

= 2A

Again, `"I" = ("ne")/"t"`

or 2 = ne(since t = 1 s)

or n = `2/e`

= `2/(1.6 × 10^−19)`

∴ n = 1.25 × 10¹⁹