Question

How many electrons per second pass a point in a circuit when a current of 1.60A is established in the circuit? (Charge on an electron = 1.6x 10^-19 C)

Answer 1

The information given is

The charge of the electron is $|e^{-}|= 1.6x 10^{-19}\;C$

The electric current is $I=1.60\;\text{A}$

The electric current is equal to the number of electric charges that pass through a wire in a certain time, that is to say.

$I=\dfrac{Q}{t}$

Where.

$Q$ is the electric charge.

$t$ is the time.

Obtaining the expression for the electric charge.

$I=\dfrac{Q}{t}\\ \dfrac{Q}{t}=I\\ Q=I\;t$

Evaluating numerically for t = 1 s

$Q=I\;t\\ Q=1.60\;\text{A}\times 1\;\text{s}\\ Q=1.60\;\text{C}$

The total electrical charge that passes is $Q=1.60\;\text{C}$

Now, the number of electrons is given by

$N=\dfrac{Q}{|e^{-}|}$

Where.

$Q$ is the electric charge.

$|e^{-}|$ is the magnitude of the electric charge of an electron.

Evaluating numerically.

$N=\dfrac{Q}{|e^{-}|}\\ N=\dfrac{1.60\;\text{C}}{1.6x 10^{-19}\;C}\\ \\ N=1\times 10^{19}\;\text{Electrons }$

Finally.

The number of electrons is $\displaystyle \color{red}{\boxed{1\times 10^{19}\;\text{Electrons }}}$