A photocell is illuminated by a small lamp pl | vedclass

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

Question

(A) In the photoelectric effect,the number of photoelectrons emitted per second is directly proportional to the intensity of the incident light.Intens

Vedclass · Accepted Answer

one-fourth of the initial number.

Vedclass · Answer

(A) In the photoelectric effect,the number of photoelectrons emitted per second is directly proportional to the intensity of the incident light.Intensity $(I)$ of light from a point source follows the inverse square law,$I \propto \frac{1}{r^2}$,where $r$ is the distance from the source.When the distance is increased from $r_1 = 1 \ m$ to $r_2 = 2 \ m$,the intensity becomes $I_2 = I_1 	imes (\frac{r_1}{r_2})^2 = I_1 	imes (\frac{1}{2})^2 = \frac{I_1}{4}$.Since the number of emitted photoelectrons is proportional to the intensity,the number of emitted electrons will become one-fourth of the initial number.

$A$ photocell is illuminated by a small lamp placed at a distance of $1 \ m$. If the lamp is shifted to a distance of $2 \ m$,then the number of emitted electrons will be:

Similar Questions

The anode voltage of a photocell is kept fixed. The frequency of the light falling on the cathode is gradually increased. Then the correct graph which shows the variation of photo current $I$ with the frequency $\nu$ of incident light is

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.

The value of the stopping potential in the following diagram is ......... $V$.

When monochromatic radiation of intensity $I$ falls on a metal surface, the number of photoelectrons and their maximum kinetic energy are $N$ and $K$ respectively. If the intensity of radiation is $2I$, the number of emitted electrons and their maximum kinetic energy are respectively

The graph shows the variation of photocurrent with anode potential for four different radiations. Let $I_a, I_b, I_c$ and $I_d$ be the intensities and $f_a, f_b, f_c$ and $f_d$ be the frequencies for the curves $a, b, c$ and $d$ respectively,then

Vedclass Test Series

Exam Paper Generator

Online Exam Module