The spin states of a nucleus of an atom in absence of applied magnetic field have:

Explanation

In the absence of an applied magnetic field, the spin states of a nucleus of an atom have equal energies. Each spin state corresponds to a possible orientation of the nuclear spin angular momentum, but without the influence of an external magnetic field, these states remain at the same energy level. When an external magnetic field is applied, the energy levels split, a phenomenon known as nuclear Zeeman splitting. This splitting occurs because the magnetic field interacts with the magnetic moment associated with the nuclear spin, resulting in different energy levels.The incorrect options fail to acknowledge that, without an external magnetic field, the energy levels remain equal. Option A suggests different energies, which only occurs when a magnetic field is present. Option C claims zero energies, overlooking the inherent energies due to nuclear spin. Option D suggests high energies, which is inaccurate as the energy levels without a magnetic field are typically low.