High School

How many electrons must be removed from a piece of metal to give it a positive charge of [tex]1 \times 10^{-6} \, \text{C}[/tex]?

A. [tex]6.25 \times 10^{12}[/tex]
B. [tex]6.25 \times 10^{14}[/tex]
C. [tex]6.25 \times 10^{16}[/tex]
D. [tex]6.25 \times 10^{18}[/tex]

Answer :

Final answer:

To give a piece of metal a positive charge of 1 x 10^-6 C, 6.25 x 10^12 electrons must be removed, based on the charge of a single electron (1.602 x 10^-19 C). So the correct answer is option (A).

Explanation:

To determine how many electrons must be removed from a piece of metal to give it a positive charge of 1 x 10-6 C, we can use the relationship that the total charge Q is the product of the number of electrons removed, ne, and the elementary charge, e. The charge of a single electron is approximately -1.602 x 10-19 C. To find the number of electrons that corresponds to a charge of 1 x 10-6 C, we use the equation.

Q = ne * e

Therefore,

ne = Q / e

ne = (1 x 10-6 C) / (1.602 x 10-19 C/electron)

ne = 6.25 x 1012 electrons

So, the correct answer is (a) 6.25 x 1012 electrons.