Question

A sphere of work function `phi=4.6 eV` is suspended in a vacuum number by an insulating thread. Radiation of wavelength `lambda =0.2 mum` stricke on the sphere. The maximum electric pontential of the sphere will be
A. 4.6 V
B. 6.2 V
C. 1.6 V
D. 3.2 V

Answer 1

Correct Answer - A
`E_("Photon")=(12400)/(lambda(Å))=(12400)/(2000)=6.2 eV`
`KE_("max")=E_("Photon")-phi=1.6 eV`
Maximum potential of sphere =1.6 eV