When 0.50; mathring{A} X-rays strike a materi | vedclass

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

Question

(B) The velocity $v$ of the photoelectrons is given by the magnetic force providing the centripetal force: $evB = m\frac{v^2}{R} \implies v = \frac{eB

Vedclass · Accepted Answer

$6.2$

Vedclass · Answer

(B) The velocity $v$ of the photoelectrons is given by the magnetic force providing the centripetal force: $evB = m\frac{v^2}{R} \implies v = \frac{eBR}{m}$.The kinetic energy $K$ of the photoelectrons is $K = \frac{1}{2}mv^2 = \frac{e^2B^2R^2}{2m}$.Substituting the values: $e = 1.6 	imes 10^{-19}\; C$,$B = 2 	imes 10^{-2}\; T$,$R = 23 	imes 10^{-3}\; m$,$m = 9.1 	imes 10^{-31}\; kg$:$K = \frac{(1.6 	imes 10^{-19})^2 	imes (2 	imes 10^{-2})^2 	imes (23 	imes 10^{-3})^2}{2 	imes 9.1 	imes 10^{-31}} \approx 2.97 	imes 10^{-15}\; J$.Converting to $keV$: $K = \frac{2.97 	imes 10^{-15}}{1.6 	imes 10^{-19}} \approx 18.56\; keV$.The energy of the incident photon is $E = \frac{hc}{\lambda} = \frac{12.4\; keV \cdot \mathring{A}}{0.50\; \mathring{A}} = 24.8\; keV$.The binding energy $BE$ is given by $BE = E - K = 24.8\; keV - 18.6\; keV = 6.2\; keV$.

Similar Questions

If the minimum wavelength of an $X$-ray is $2 \mathring{A}$,then the potential difference between the anode and the cathode is ...... $kV$.

$X$-rays and $\gamma$-rays of the same energies may be distinguished by

The wavelengths of $K_{\alpha}$ $X$-rays of two metals $A$ and $B$ are $\frac{4}{1875R}$ and $\frac{1}{675R}$ respectively,where $R$ is Rydberg's constant. The number of elements lying between $A$ and $B$ according to their atomic numbers is

$X$-rays are produced by accelerating electrons through a potential difference $V$ and letting them strike a metal target of atomic number $Z$. The highest frequency of the $X$-rays produced is proportional to:

When the atomic number of the first target is $Z_1 = 64$ and the atomic number of the second target is $Z_2 = 80$,the approximate ratio of the wavelengths of the $K_{\alpha,1}$ and $K_{\alpha,2}$ radiations is .......

Vedclass Test Series

Exam Paper Generator

Online Exam Module