A photoelectric cell is illuminated by a poin | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The intensity $I$ of light from a point source at a distance $d$ is given by $I = \frac{P}{4\pi d^2}$,where $P$ is the power of the source.Thus,$I

Vedclass · Accepted Answer

Become four times

Vedclass · Answer

(B) The intensity $I$ of light from a point source at a distance $d$ is given by $I = \frac{P}{4\pi d^2}$,where $P$ is the power of the source.Thus,$I \propto \frac{1}{d^2}$.When the distance is reduced to $d' = d/2$,the new intensity $I'$ becomes $I' = \frac{P}{4\pi (d/2)^2} = \frac{P}{4\pi (d^2/4)} = 4 	imes \frac{P}{4\pi d^2} = 4I$.The number of photoelectrons emitted per second is directly proportional to the intensity of the incident light $(N \propto I)$.Since the intensity becomes $4$ times,the number of electrons emitted per second will also become $4$ times the original value.

$A$ photoelectric cell is illuminated by a point source of light kept at a distance $d$. If the distance is reduced to $d/2$,then the number of electrons emitted per second will be:

Similar Questions

Assertion: The photoelectrons produced by a monochromatic light beam incident on a metal surface have a spread in their kinetic energies.
Reason: The work function of the metal is its characteristic property.

$A$ photocell is illuminated by a small source of light placed at a distance of $1 \ m$. When the same source of light is placed at a distance of $1/2 \ m$,the number of electrons emitted by the photocathode will .......

Light of wavelength $4000 Å$ is incident on a sodium surface for which the threshold wavelength of photoelectrons is $5420 Å$. The work function of sodium is (in $eV$)

$A$ caesium photocell,with a steady potential difference of $60 \ V$ across it,is illuminated by a bright point source of light $50 \ cm$ away. When the same light source is placed $1 \ m$ away,the photoelectrons emitted from the cell:

Consider the two following statements $A$ and $B$ and identify the correct choice given in the answers:

Vedclass Test Series

Exam Paper Generator

Online Exam Module