Five elements `A , B , C , D` and `E` have work functions `1.2 eV , 2.4 eV , 3.6 eV , 4.8 eV` and `6 eV` respectively . If light of wavelength `4000 Å` is allowed to fall on these elements , then photoelectrons are emitted by

Options

A. `A , B` and `C`
B. `A , B , C , D` and `E`
C. `A` and `B`
D. Only `E`

Answer

C

Explanation

`E = (12375)/(4000) = 3.09 eV` Photoelectrons emits if energy of incident light gt work function.