Question

how many electrons are passing per second in a circuit in which there is a current of 5A?​

Answer 1

Given :

Current flowing in the circuit = 5A

To Find :

No. of electrons passing per second in a circuit

Solution :

We know,

Current (i) = [No of electrons(n) × charge of the electron (e)] ÷ time(t)                                                      

or,                            i  = $\frac{ne}{t}$

or,                           5  = $\frac{n * 1.6* 10^{-19} }{1}$ ( e = 1.6 × $10^{-19}$C)

or,                           n  = $\frac{5}{1.6 * 10^{-19} }$

∴                             n  =  3.125 × $10^{19}$

∴ 3.125 × $10^{19}$ electrons are passing through the circuit per second.

   

Answer 2

Given:

Current in circuit (I) = 5 Ampere

Time duration (t) = 1 second

Charge on one electron (e) = $1.6*10^{-19} Coulomb$

To find: Number of electrons

Calculation:

• Current is defined as the flow of charge per unit time.
• Charge is given as Q = n * e, where n is the number of electrons, e is the electronic charge on one electron and Q is the total charge in circuit.
• $Current=\frac{charge}{time} =\frac{Q}{t} =\frac{n*e}{t}$

$I=\frac{n*1.6*10^{-19} }{1} \\5=n*1.6*10^{-19}\\3.125*10^{19} =n$

Answer:

Number of electrons passing per second in the circuit are $3.125*10^{19}$.