Which of the metal sodium and copper will be suitable for photelectric cell using light of
Channel: Doubtnut
Date: 2020-08-30

Which of the metal sodium and copper will be suitable for photelectric cell using light of wavelength `4000 Å`. The work functions of sodium and copper are respectively 2.0 eV and 4.0 eV. Take `h=6.6 xx 10^(-34) Js, c = 3.0 xx 10^(8) ms^(-1)` and 1 eV = `1.6 xx 10^(-19) J`