Two streams of photons,possessing energies eq | 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 $K_{max}$ is given by $K_{max} = E - \phi$,where $E$ is the energy of th

Vedclass · Accepted Answer

$2: 3$

Vedclass · Answer

(C) According to Einstein's photoelectric equation,the maximum kinetic energy $K_{max}$ is given by $K_{max} = E - \phi$,where $E$ is the energy of the incident photon and $\phi$ is the work function.For the first case,$E_1 = 5\phi$. Therefore,$K_{max,1} = 5\phi - \phi = 4\phi$.Since $K_{max,1} = \frac{1}{2}mv_1^2$,we have $\frac{1}{2}mv_1^2 = 4\phi$.For the second case,$E_2 = 10\phi$. Therefore,$K_{max,2} = 10\phi - \phi = 9\phi$.Since $K_{max,2} = \frac{1}{2}mv_2^2$,we have $\frac{1}{2}mv_2^2 = 9\phi$.Taking the ratio of the two equations:$\frac{\frac{1}{2}mv_1^2}{\frac{1}{2}mv_2^2} = \frac{4\phi}{9\phi}$$\frac{v_1^2}{v_2^2} = \frac{4}{9}$Taking the square root on both sides,we get $\frac{v_1}{v_2} = \frac{2}{3}$.Thus,the ratio of the maximum velocities is $2:3$.

Two streams of photons,possessing energies equal to $5$ and $10$ times the work function of a metal,are incident on the metal surface successively. What is the ratio of the maximum velocities of the photoelectrons emitted in the two cases,respectively?

Similar Questions

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

In the experiment of photoelectric effect, $K_{max}$ for a photoelectron is $K_0$. If the frequency of light is doubled, then $K_{max}$ is $3K_0$. What would be the value of $K_{max}$ if the frequency of light is tripled? (in terms of $K_0$)

Sodium and copper have work functions of $2.3 \ eV$ and $4.5 \ eV$ respectively. The ratio of their threshold wavelengths is approximately .......

When the energy of the incident radiation is increased by $20\%$,the kinetic energy of the photoelectrons emitted from a metal surface increases from $0.5\, eV$ to $0.8\, eV$. The work function of the metal is ............. $eV$.

Vedclass Test Series

Exam Paper Generator

Online Exam Module