Question

2. For coulomb force to be operative the least size of
atom will be
(a) 10-12 m
(b) 10-15 m
(c) 10-10 m
(d) 10-8 m
[VMMC 2007)​

Answer 1

Answer:

10-15 m

it's the answer of this question

Answer 2

The answer is b) 10⁻¹⁵ m

The reason will be:

• The nuclear force is effective within the atomic diameter.
• In a nucleus, the positively charged protons and the electrically neutral neutrons exist in minimal space (≈10⁻¹⁵m).
• Naturally, some forces are operating within the nucleus, which binds the nucleons together.
• According to Coulomb's law, these forces are F=kq₁q₂/r²
• They are concise range, which means these forces are effective for a very short distance only that is within the nuclear diameter =10⁻¹⁵m.