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For \( \mathrm{He^+} \), a transition takes place from the orbit of radius \( 105.8 \, \mathrm{pm} \) to the orbit of radius \( 26.45 \, \mathrm{pm} \). The wavelength (in \( \mathrm{nm} \)) of the emitted photon during the transition is \( \_\_\_\_\_ \).
[Use: Bohr radius, \( a = 52.9 \, \mathrm{pm} \);
Rydberg constant, \( R_H = 2.2 \times 10^{-18} \, \mathrm{J} \);
Planck’s constant, \( h = 6.6 \times 10^{-34} \, \mathrm{J\,s} \);
Speed of light, \( c = 3 \times 10^{8} \, \mathrm{m\,s^{-1}} \)]

According to Bohr’s model, the highest kinetic energy is associated with the electron in the:

The \( 2s \) and the \( 2p \) orbital energies of hydrogen atom are \( E_{2s}(\mathrm{H}) \) and \( E_{2p}(\mathrm{H}) \), respectively. The \( 2s \) and the \( 2p \) orbital energies of lithium atom are \( E_{2s}(\mathrm{Li}) \) and \( E_{2p}(\mathrm{Li}) \), respectively. The correct option(s) about the orbital energies is(are):

Consider a helium (He) atom that absorbs a photon of wavelength \( 330 \, \text{nm} \). The change in the velocity (in \( \text{cm s}^{-1} \)) of He atom after the photon absorption is ____________ .
(Assume: Momentum is conserved when photon is absorbed.)
Use: Planck constant = \( 6.6 \times 10^{-34} \, \text{J s} \), Avogadro number = \( 6 \times 10^{23} \, \text{mol}^{-1} \), Molar mass of He = \( 4 \, \text{g mol}^{-1} \)