Q. 175.0( 1 Vote )

# Find the maximum magnitude of the linear momentum of a photoelectron emitted when light of wavelength 400 nm falls on a metal having work function 2.5 eV.

Answer :

Given, wavelength λ =400×

Work function=2.5eV

From photoelectric equation,

Where K is kinetic energy,

h is Planck’s constant,

c is speed of light,

Ф is the work function,

is the wavelength of light.

⇒

⇒

⇒

We also know that,

Where P is linear momentum and m is mass of electron

⇒

⇒

⇒

⇒ .

Rate this question :

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.

HC Verma - Concepts of Physics Part 2Do all the electrons that absorb a photon come out as photoelectrons?

Physics - ExemplarA horizontal cesium plate (ϕ = 1.9 eV) is moved vertically downward at a constant speed v in a room full of radiation of wavelength 250 nm and above. What should be the minimum value of v so that the vertically upward component of the velocity is non-positive for each photoelectron?

HC Verma - Concepts of Physics Part 2Consider the situation of the previous problem. Consider the fastest electron emitted parallel to the large metal plate. Find the displacement of this electron parallel to its initial velocity before it strikes the large metal plate.

HC Verma - Concepts of Physics Part 2