A metal plate is exposed to light with wavelength λ. It is observed that electrons are ejected from the surface of the plate. When a retarding uniform electric field E is applied, no electron can move away from the plate farther than a certain distance d. Then the threshold wavelength λ0 for the material of plate is (e is the electronic charge, h is the Plank’s constant and c is the speed of light.)

A metal plate is exposed to light with wavelength λ. It is observed t

1.	A metal plate is exposed to light with wavelength λ. It is observed that electrons are ejected from the surface of the plate. When a retarding uniform electric field E is applied, no electron can move away from the plate farther than a certain distance d. Then the threshold wavelength λ0 for the material of plate is (e is the electronic charge, h is the Plank’s constant and c is the speed of light.)
Answer» A metal plate is exposed to light with wavelength $λ$ . It is observed that electrons are ejected from the surface of the plate. When a retarding uniform electric field $E$ is applied, no electron can move away from the plate farther than a certain distance $d$ . Then the threshold wavelength $λ_{0}$ for the material of plate is ( $e$ is the electronic charge, $h$ is the Plank’s constant and $c$ is the speed of light.)

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