The binding energy (BE) per nucleon for an element is 7.14 MeV . If the BE of element is 28.6 MeV , then the number of nucleons in the element is

Let $G, W, E$ and $S$ be relative strength of gravitational, weak-nuclear, electromagnetic and strong-nuclear forces, respectively. Which of the correct statement?

In the Bohr model an electron of mass $m$ moves in a circular orbit around the proton. Considering the orbiting electron to be a circular current loop, the magnetic moment of the hydrogen atom, when the electron is in $n$th excited state. (Assume, $h=$ Planck's constant)

A radioactive element which can decay by two processes, has half-life $t_1$ for first process and half-life $t_2$ for second process. Let $\langle t\rangle$ be the effective average-life of this element. Which of the following is correct?