From the statements given below : (A) The angular momentum of an electron in nth orbit is an integral multiple of h. (B) Nuclear forces do not obey inverse square law. (C) Nuclear forces are spin dependent. (D) Nuclear forces are central and charge independent. (E) Stability of nucleus is inversely proportional to the value of packing fraction. Choose the correct answer from the options given below :
Each statement from the question is examined to identify the correct answer:
(A) The angular momentum of an electron in the nth orbit is an integer multiple of h. Bohr's atomic model posits that an electron's angular momentum in the nth orbit is quantized, expressed as \(L = n\hbar = \frac{nh}{2\pi}\). This statement is accurate.
(B) Nuclear forces do not adhere to the inverse square law. Nuclear forces are short-range and do not diminish with distance according to the inverse square law, unlike gravitational and electrostatic forces. This statement is accurate.
(C) Nuclear forces are spin dependent. The spin orientation of the interacting nucleons (neutrons and protons) influences nuclear forces, making them spin-dependent. This statement is accurate.
(D) Nuclear forces are central and charge independent. While nuclear forces are charge independent, they are not exclusively central forces. A central force acts along the line connecting particle centers, which does not accurately describe nuclear forces. Consequently, this statement is inaccurate.
(E) The stability of the nucleus is inversely proportional to the packing fraction. The packing fraction is calculated using the formula: \(\text{Packing fraction} = \frac{\text{(Mass of nucleus)} - \text{(Mass number)}}{\text{(Mass number)}}\). A lower packing fraction generally correlates with higher binding energy per nucleon, signifying greater nuclear stability. Therefore, this statement is accurate.
Upon reviewing the statements, (A), (B), (C), and (E) are identified as correct. The correct selection is:
