Question

calculate the no of electrons flowing through the cross section of conductor when current of 20 ma flows for 50 seconds. ​

Answer 1

Answer:

${\large{\bf{\red{\clubs{\underline{Given :}}}}}}$

Given;-:-

• Current= I= 20mA
• Time taken=t=50 sec

• Also we know that,

• Charge of electron , e=1.6×10^-19

To find :-

• Number of electron

Explanation :-

• Here first converting the unit current into A.
• 1mA=0.001A
• 20mA=20×0.001
• 20mA= 0.02A

Here we can use the formula of :-

☆I=Q/T

• I denote current
• Q denotes charge
• T denotes time

• Also,
• I=ne/T

• Now applying the values

• 0.02 = n×1.6×10^-19/50
• 0.02×50=n×1.6×10^-19
• 1 /1.6×10^-19

• 0.625×10^19=n
• n = 6.25×10^18.

Therefore ,

• Total number of electrons =6.25×10^18.

Hope it helps u mate .

Thank you .

Answer 2

Answer:

6.25 × 10¹⁸ electrons is the required answer

Explanation:

According to the Question

It is given that,

• Current ,I = 20ma
• Time ,t = 50s

we need to calculate the number of electrons flowing through the section of conductor .

Conversion of current into Ampere

→ 1 Ampere = 1000ma

→ 20ma = 20/1000 = 0.02 A

Firstly we calculate the charge flows through the condutor .

• I = Q/t

where,

I denote Current

Q denote charge

t denote time

Substitute the value we get

➻ 0.02 = Q/50

➻ 0.02 × 50 = Q

➻ Q = 0.02 × 50

➻ Q = 1 C

Now, Calculating the number of electrons flowing through the cross section of the condutor .

As we know that the charge on electron

→ e = 1.6 × 10⁻¹⁹

as we know

• Q = ne

where,

Q denote Charge

N denote number of electrons

e denote charge on a electron

Substitute the value we get

➻ 1 = n × 1.6 × 10⁻¹⁹

➻ 1/1.6*10⁻¹⁹ = n

➻ n = 0.625 × 10¹⁹

➻ n = 6.25×10¹⁸ electrons .

• Hence, the number of electrons will be 6.25×10¹⁸ electrons.