Question

Q. If light of wavelength 412.5 nm is incident on each of the metals given below, which ones will show photoelectric emission and why ?



Metal

Work Function (eV)



Na

1.92



K

2.15



Ca

3.20



Mo

4.17

Answer 1

use

$hc \div lamda - work \: funtion$

if it is positive the metal can show photo electricity