The strong nuclear force has which of the following PROPERTIES?
AIt is a long-range force, extending to atomic distances
BIt is attractive at all separations and depends only on charge
CIt is a short-range force (≲ 10⁻¹⁵ m) and is CHARGE-INDEPENDENT
DIt is purely repulsive between nucleons
Answer & Solution
Correct answer: C. It is a short-range force (≲ 10⁻¹⁵ m) and is CHARGE-INDEPENDENT
1. NCERT §13.5 lists the key properties of the strong nuclear force.
2. SHORT-RANGE: the force becomes significant only when nucleons are within about 1 fm ($10^{-15}\,\text{m}$); beyond a few fm it is essentially zero.
3. CHARGE-INDEPENDENT: the force between a p-p, p-n, or n-n pair is the same at the same separation; it acts on the nucleon regardless of electric charge.
4. MUCH STRONGER than the electromagnetic force at nucleonic distances — this is why the nucleus holds together against the proton-proton Coulomb repulsion.
5. Option A confuses it with gravity/electromagnetism. Option B is wrong on charge-dependence. Option D ignores that the strong force is attractive at the relevant scales (it becomes repulsive only at extremely short ranges, $< 0.4\,\text{fm}$, but that's not the dominant behaviour).
_Source: NCERT Class 12 Physics Part 2, Ch 13, §13.5 (Nuclear Force), p. 7–8._
Related questions
The activity of a radioactive sample drops from $4000\,\text{decays/s}$ to $500\,\text{decWhy is iron the threshold beyond which heavy-nucleus FISSION releases energy, but nuclei lThe total binding energy of $\,^{16}_{8}\mathrm{O}$ is approximately $127.6\,\text{MeV}$. A radioactive sample has half-life $T_{1/2} = 5$ years. Starting with $N_0$ undecayed nuclIn BETA-MINUS ($\beta^-$) decay, the parent nucleus emits an electron AND another particleWhen a nucleus $\,^{A}_{Z}\mathrm{X}$ undergoes ALPHA decay, the daughter nucleus hasLooking at the binding energy per nucleon vs mass number ($A$) curve, the binding energy pThe energy equivalent of one unified atomic mass unit (1 u) is closest to