A certain metallic surface is illuminated wit | vedclass

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

Question

(B) According to Einstein's photoelectric equation,the maximum kinetic energy $K_{max} = eV_s = \frac{hc}{\lambda} - \phi_0$,where $\phi_0$ is the wor

Vedclass · Accepted Answer

$4\lambda$

Vedclass · Answer

(B) According to Einstein's photoelectric equation,the maximum kinetic energy $K_{max} = eV_s = \frac{hc}{\lambda} - \phi_0$,where $\phi_0$ is the work function.Case $(i)$: For wavelength $\lambda$,stopping potential is $3V_0$:$3eV_0 = \frac{hc}{\lambda} - \phi_0$  ......... $(1)$Case $(ii)$: For wavelength $2\lambda$,stopping potential is $V_0$:$eV_0 = \frac{hc}{2\lambda} - \phi_0$  ......... $(2)$Multiply equation $(2)$ by $3$:$3eV_0 = \frac{3hc}{2\lambda} - 3\phi_0$  ......... $(3)$Equating $(1)$ and $(3)$:$\frac{hc}{\lambda} - \phi_0 = \frac{3hc}{2\lambda} - 3\phi_0$$2\phi_0 = \frac{3hc}{2\lambda} - \frac{hc}{\lambda} = \frac{hc}{2\lambda}$$\phi_0 = \frac{hc}{4\lambda}$Since the threshold wavelength $\lambda_0 = \frac{hc}{\phi_0}$,substituting $\phi_0$:$\lambda_0 = \frac{hc}{hc / 4\lambda} = 4\lambda$.

Similar Questions

The stopping potential for a photoelectric emission process is $10 \ V$. The maximum kinetic energy of the electrons ejected in the process is [Charge on electron $e = 1.6 \times 10^{-19} \ C$]

When a light of wavelength $\lambda$ falls on the emitter of a photocell,the maximum speed of emitted photoelectrons is $V$. If the incident wavelength is changed to $2\lambda / 3$,the maximum speed of the emitted photoelectrons will be:

The retarding potential necessary to stop the emission of photoelectrons,when a target material of work function $1.24 eV$ is irradiated with light of wavelength $4.36 \times 10^{-7} m$ is (in $eV$)

The work function of caesium is $2.14\, eV$. Find the wavelength of the incident light if the photo current is brought to zero by a stopping potential of $0.60\, V$. (Result in $nm$)

Light of incident frequency $2$ times the threshold frequency is incident on a photosensitive material. If the incident frequency is made $\left(\frac{1}{3}\right)^{\text{rd}}$ and intensity is doubled,then the photoelectric current will

Vedclass Test Series

Exam Paper Generator

Online Exam Module