Magnetic Moment of the Hydrogen Atom. In the Bohr model of the hydrogen atom (see Section $38.5 ),$ in the lowest energy state the electron orbits the proton at a speed of $2.2 \times$ $10^{6} \mathrm{m} / \mathrm{s}$ in a circular orbit of radius $5.3 \times 10^{-11} \mathrm{m}$ (a) What is the orbital period of the electron? (b) If the orbiting electron is considered to be a current loop, what is the current $I ?$ (c) What is the magnetic moment of the atom due to the motion of the electron?