Question

A current of 4A flows through a wire. Number of electrons which will pass through a given point in each second are

Answer 1

Current (i) is given by the formula
i = nQ/t

Where
n : Number of charged particles
Q : Charge of the particle (1.6 × 10⁻¹⁹ C for electron)
t : Time

n = it / Q
= 4 A × 1 s / (1.6 × 10⁻¹⁹ C)
= 2.5 × 10¹⁹

∴ 2.5 × 10¹⁹ electrons pass in 1 second.

Answer 2

→ Formula of Current,

i = nQ/t

--------------------

→ n = it / Q

= 4 A × 1 s / (1.6 × 10⁻¹⁹ C)

= 2.5 × 10¹⁹

-------------------

∴ 2.5 × 10¹⁹ electrons pass in 1 second.