Question

HOW MANY ELECTRONS WOULD HAVE TO REMOVE FROM COPPER PENNY TO LEAVE IT WITH POSITIVE CHARGE OF 10 TO POWER -7

Answer 1

Answer:

6.25 × 10¹¹ electrons should be removed from copper penny.

Explanation:

To find-----> How many electrons would have to be removed from a copper penny to leave it with a positive charge of 10⁻⁷ C .

Concept used -----> We know that, from

Qunatization of electric charge ---> The total charge on a body is integral multiple of charge on an electron or a proton ie

q = n e

q = Charge on body

n = number of electron

e = Charge on one electron = 1.6 × 10⁻¹⁹ C

Solution----> We know that ,

Charge on one electron = 1.6 × 10⁻¹⁹ C

Charge on copper penny after removal of electrons = 10⁻⁷ C

Let , number of electrons removed from copper penny be n so ,

q = n e

=> 10⁻⁷ = n × 1.6 × 10⁻¹⁹

=> n = 10⁻⁷ / 1.6 × 10⁻¹⁹

=> n = 10⁻⁷ × 10¹⁹ / 1.6

=> n = 0.625 × 10¹⁹ ⁻ ⁷

=> n = 0.625 × 10¹²

=> n = 6.25 × 10¹¹

So 6.25 × 10¹¹ electrons should be removed from penny.