Question

2.4 into 10 to the power 20 electrons flow through a circuit in 10 hours calculate the magnitude of the current​

Answer 1

Solution:

Since we are given:

Number of electrons passing = n = 2.4x10^20

Time taken = t = 10hours

Required:

Magnitude of current = I= ?

Thus by definition of current we know that current is the magnitude of charges passed through any conductor per second; thus,

I = magnitude of charges(q)/t --(i)

Now for magnitude of charges:

By the law of quantization of charges, we know that any charge is actually the integral multiple of basic charge of electron;

q = ne

Where,

'q' is any enclosed charge, n= 0,1,2,3,... and e is the basic charge of electron, which is 1.609x10^-19Coulombs.

Thus, upon inserting the values in above equation;

q = (2.4x10^20)(1.609x10^-19)

=> q = 3.86x10

=> q = 38.6Coulombs,

Now equation(i) implies:

I = q/t

=> I = 38.6/10hours

But for current, time should be in seconds; thus, 10 hours = 36000s.

=> I = 38.6/36000

=> I = 0.0010722Amperes.