When a certain metal surface is illuminated w | vedclass

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

Question

(C) According to Einstein's photoelectric equation,the maximum kinetic energy $K_{max}$ of the emitted photoelectrons is given by $K_{max} = h v - h v

Vedclass · Accepted Answer

$v/3$

Vedclass · Answer

(C) According to Einstein's photoelectric equation,the maximum kinetic energy $K_{max}$ of the emitted photoelectrons is given by $K_{max} = h v - h v_0$,where $v_0$ is the threshold frequency.Since the stopping potential $V_s$ is related to the maximum kinetic energy by $K_{max} = e V_s$,we have $e V_s = h v - h v_0$ ... $(1)$.For the second case,with frequency $v/2$ and stopping potential $V_s/4$,we have $e(V_s/4) = h(v/2) - h v_0$ ... $(2)$.From equation $(1)$,$e V_s = h v - h v_0$. Substituting this into equation $(2)$ multiplied by $4$:$e V_s = 4(h v/2 - h v_0) = 2h v - 4h v_0$.Equating the two expressions for $e V_s$:$h v - h v_0 = 2h v - 4h v_0$.Rearranging the terms: $3h v_0 = h v$.Therefore,$v_0 = v/3$.

When a certain metal surface is illuminated with light of frequency $v$,the stopping potential for the photoelectric current is $V_s$. When the same surface is illuminated by a light of frequency $v/2$,the stopping potential is $V_s/4$. The threshold frequency of photoelectric emission is

Similar Questions

From the figure describing the photoelectric effect,we may infer correctly that:

$A$ point source of light is used in a photoelectric effect. If the source is moved farther from the emitting metal, the stopping potential:

The variation of stopping potential $(V_0)$ as a function of the frequency $\nu \ (\times 10^{14} \ Hz)$ of the incident light for a metal is shown in the figure. The work function of the surface is $........... \ eV$.

Two identical photo-cathodes receive light of frequencies $f_1$ and $f_2$. If the velocities of the photo-electrons (of mass $m$) coming out are $v_1$ and $v_2$ respectively,then:

Vedclass Test Series

Exam Paper Generator

Online Exam Module