Question

Number of electrons in 10 coulomb charge is equal to:
1.  625 × 1016
2.  625 × 1017
3.  625 × 1015
4.  6.25 × 1017

Answer 1

Correct Answer - Option 2 :  625 × 1017

CONCEPT:

Electric Charge

• It is defined as the intrinsic property of certain fundamental particles like electrons, proton, etc, due to which they produce electric and magnetic effects.
• Types of electric charge
  1. ​Positive charge: A body having a deficiency of electrons.
  2. ​Negative charge: A body having an excess of electrons.
• Properties of electric charge
  • Like charges repel and unlike charges attract each other.
  • A charge is a scalar quantity.
  • A charge is always quantized.
  • A charge will always remain conserved.
  • A charge is always associated with mass.
  • The unit of charge is the coulomb.

⇒ 1 coulomb= charge on 625×1016 electrons

CALCULATION:

We know that the number of electrons in 1-coulomb charge is,

⇒ N = 625×1016 electrons

So the number of electrons in 10-coulomb charge is,

⇒ N' = 10 × 625 × 10¹⁶ electrons

⇒ N' = 625 × 10¹⁷ electrons

• Hence, option 2 is correct.