--%>

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 : Explain Ohms law Ohm's law (G. Ohm;

    Ohm's law (G. Ohm; 1827): The ratio of the potential difference among the ends of a conductor to the current flowing via it is constant; the constant of proportionality is termed as the resistance, and is distinct for different materials.

  • Q : Define Cosmological redshift

    Cosmological redshift: The effect where light emanates from a distant source appears redshifted since of the expansion of the space time itself.

  • Q : Velocity of the particle Determine the

    Determine the Velocity of the particle in terms of component veocities?

  • Q : Define Static limit Static limit : The

    Static limit: The distance from a rotating black hole where no spectator can possibly stay at rest (with respect to the far-away stars) since of inertial frame dragging; this area is external of the event horizon, apart from at the poles where it meet

  • Q : What do you mean by the term fusion

    What do you mean by the term fusion reaction?

  • 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 multi level TDM Ten sources,

    Ten sources, six with a bit rate of 200 Kbps and four with a bit rate of 400Kbps are to be combined using multi level TDM  with no sync bits. Answer the questions below about the final phase of multiplexing: a

  • Q : Define Grandfather paradox Grandfather

    Grandfather paradox: The paradox proposed to discount time travel and exhibit why it violates causality. State that your grand-father makes a time machine. In the current time, you employ his time machine to go back in time a few decades to a point be

  • Q : Define Relativity principle Relativity

    Relativity principle: The principle, utilized by Einstein's relativity theories, that the laws of physics are similar, at least qualitatively, in all frames. That is, there is no frame which is better (or qualitatively any different) from any other. T

  • 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).