Question

all about photoelectric effect ???? plz help

Answer 1

Hey friend:+--/


just look:-
"The phenomenon of ejection of electrons from the surface of a metal when light of suitable frequency strikes on it, is called photoelectric effect.
The emitted electrons are called photoelectron.
Experimental studies of photoelectric effect under different conditions led to the following important observations:----
(i) The electrons are ejected from the metal surface as soon as the beam of light strikes the surface. .
(ii) For each metal, certain minimum frequency
light is needed to eject the electrons. This is known as threshold frequency and it is different for different metal.
(iii) The kinetic energy of the ejected electrons is
directly proportional to the frequency of the incident radiation and it is independent of its intensity.
(iv) The number of electrons ejected per second from the metal surface depends upon the intensity or brightness of incident radiation but does not depend upon its frequency.

Answer 2

Photoelectric effect is the emission of electrons when light is thrown on an object. Electrons which are emitted in this effect are known as photo electrons.
they are used in:-
1.Image sensors.
2.Gold-leaf electroscope.
3.Phtoelectron spectroscopy.
4.Night vision devices.

HOPE THIS HELPS!