--%>

Explain Photoelectric effect

Photoelectric effect: An effect described by A. Einstein that demonstrates that light seems to be made up of particles, or photons. The light can excite electrons (termed as photoelectrons in this context) to be ejected from the metal. Light with a frequency below with a certain threshold, at any intensity, will not origin any photoelectrons to be emitted from metal. Above the frequency, photoelectrons are emitted in proportion to the intensity of the incident light.

The reason is that a photon comprises energy in proportion to its wavelength, and constant of proportionality is the Planck’s constant. Below a certain frequency -- and therefore below a certain energy -- the incident photons do not contain enough energy to knock the photoelectrons out of the metal. Over that threshold energy, termed as the work function, the photons will bang the photoelectrons out of the metal, in proportion to the number of photons (that is the intensity of the light). In higher energies and frequencies, the photoelectrons ejected get a kinetic energy equivalent to the difference among the photon's energy and the work function.

   Related Questions in Physics

  • Q : Define the term wave fronts What do you

    What do you mean by the term wave fronts? Explain in short.

  • Q : What is Wiens displacement law constant

    Wien's displacement law constant, b: It is the constant of Wien displacement law. This has the value of 2.897 756 x 10-3 m K.

  • Q : What is Bernoulli's equation

    Bernoulli's equation - In an ir-rotational fluid, the sum of static pressure, the weight of the fluid per unit mass times the height and half of the density times the velocity squared is steady all through the fluid 

  • Q : Explain Youngs experiment or

    Young's experiment: double-slit experiment (T. Young; 1801): A well-known experiment that exhibits the wave nature of light (and certainly of other particles). The light is passed from a small source into an opaque screen with the two thin slits. The

  • Q : Problem on Orbit cycle Calculate the

    Calculate the hot and cold temperature after 25 orbits. Assume a 100kg spherical spacecraft made of aluminum. Assume that the spacecraft is in an equatorial orbit. How is calculation 1 different for a spacecraft in a 90 degree (polar) orbit?

  • Q : What is Hawking temperature Hawking

    Hawking temperature: The temperature of a black hole is caused by the emission of the hawking radiation. For a black hole with mass m, it is illustrated as: T = (hbar c3)/(8 pi G k m).

  • Q : Developing an algorithm to remove noise

    sir, Would you please help me to develop an algorithm to reduce noise and to detect weak signals under water using Green's function?

  • Q : Explain Casimir effect Casimir effect

    Casimir effect (Casimir): The quantum mechanical effect, where two very big plates positioned close to each other will experience an attractive force, in the nonattendance of other forces. The cause is implicit particle-antiparticle p

  • Q : Explain Tachyon Tachyon: The purely

    Tachyon: The purely speculative particle that is supposed to travel faster than light. According to Sir Einstein's equations of special relativity, a particle with imaginary rest mass and a velocity more than c would contain a real momentum and energy

  • Q : Brewster's law Brewster's law (D.

    Brewster's law (D. Brewster) - The extent or level of the polarization of light reflected from a transparent surface is maximum whenever the reflected ray is at right angle to the refracted ray.