The stopping potential for photoelectric emission from a metal surface is 2 V when light of wavelength 400 nm is incident. What will be the stopping potential for light of wavelength 300 nm? (Planck’s constant \( h = 6.63 \times 10^{-34} \) Js, speed of light \( c = 3 \times 10^8 \) m/s, charge of electron \( e = 1.6 \times 10^{-19} \) C)