Assertion (A): The binding energy per nucleon is practically independent of the atomic number for nuclei of mass number in the range 30 to 170. This is true because for medium and heavy nuclei, the binding energy per nucleon remains approximately constant and stable in this mass range.
Reason (R): Nuclear force is short-ranged. This is true because nuclear forces act only within a very short range (of the order of a few femtometers) and are responsible for binding nucleons together. Since the stability of the binding energy per nucleon is a consequence of the short-ranged nature of nuclear forces, the reason (R) correctly explains the assertion (A).
Thus, the correct answer is \( \boxed{(1)} \).
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,

In a nuclear fission process, a high mass nuclide (A ≈ 236) with binding energy 7.6 MeV/Nucleon dissociated into middle mass nuclides (A ≈ 118), having binding energy of 8.6 MeV/Nucleon. The energy released in the process would be ____ MeV.
What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)