Consider a helium (He) atom that absorbs a photon of wavelength 330 nm. The change in the velocity (in cm s⁻¹) of He atom after the photon absorption is ___. Assume momentum is conserved when photon is absorbed. Use Planck constant = 6.6 × 10⁻³⁴ J s, Avogadro number = 6 × 10²³ mol⁻¹ and molar mass of He = 4 g mol⁻¹.