A small metal plate (work function ϕ ) is kept at a distance d from a singly ionized, fixed ion. A monochromatic light beam is incident on the metal plate and photoelectrons are emitted. Find the maximum wavelength of the light beam so that some of the photoelectrons may go round the ion along a circle.

Question

Philoid · Accepted Answer

Given, work function=Ф

Distance=d

It is also given that particle is moving in a circle

Now, from Einstein’s photoelectric equation,

⇒

On solving the above equation we get,

∴