Moseley’s Law

The element which has a $K_{\alpha }$ $x$-rays line of wavelength $1.8\mathrm{\AA }$ is $\left(R=1.1\times {10}^7 {\mathrm{m}}^{-1}, b=1\right)$ and $\left.\sqrt{\frac{5}{33}}=0.39\right)$

If $\mathrm{Ni}$ (nical) is used as target material, then ${\lambda }_{\min }$ is minimum wavelength produced in $X$-ray tube and ${\lambda }_{k\alpha }$ is the wavelength of $k_{\alpha }$ line. If the operating tube voltage is increased and $Ca$ (calsium) is used as target material in place of $Ni,$ then the difference $\left|{\lambda }_{k\alpha }-{\lambda }_{\min }\right|$ will :

A student is jogging on a straight path with the speed $5.4 \mathrm{km}$ per hour. Perpendicular to the path is kept a pipe with its opening $8 \mathrm{m}$ from the road (see figure). Diameter of the pipe is $0.45 \mathrm{m}$ At the other end of the pipe is a speaker emitting sound of $1280 \mathrm{Hz}$ towards the opening of the pipes. As the student passes in front of the pipe, she hears the speaker sound for $T$ seconds. $T$ is in the range (take speed of sound, $320 {\mathrm{ms}}^{-1}$):

What is the atomic number of the element whose wavelength of $K_{\alpha }$ line of characteristic $X-$ray is $250 \mathrm{pm}.$ (Rydberg constant $\left.=1.097\times {10}^7 {\mathrm{m}}^{-1}\right)$

The wavelength of a certain line in the $X$-rays spectrum for tungsten $\left(Z=74\right)$ is $200 \stackrel{°}{\mathrm{A}}$. What would be the wavelength of the same line for platinum $\left(Z=78\right) ?$ The screening constant $a$ is unity.

A screen is place $50 \mathrm{cm}$ from a single slit, which is illuminated with $6000 \mathrm{A}$ light. If the distance between the first and third minima in the diffraction pattern is $3 \mathrm{mm},$ the width of the slit is

Use Moseley's law with $b=1$ to find the frequency of the $K_{\alpha }X$ -rays of $La(Z=57)$. if the frequency of the $K_{\propto }X$ -rays of $Cu(Z=29)$  is known to be $1.88\times {10}^{18} \mathrm{Hz}$

The wavelength of $K_{\alpha }$ line from an element of atomic number $51$ is $\lambda$. From another element the wavelength of $K_{\alpha }$ line is $4\lambda$. What is the atomic number of second element?
 

A cobalt (atomic no. $=27$ ) target is bombarded with electrons and the wave lengths of its characteristic $X$-rays spectrum are measured. A second weak characteristic spectrum is also found due to an impurity in the target. The wavelength of the $K_{\mathit{\alpha }}$ lines are $225.0 \mathrm{pm}$ (cobalt) and $100.0 \mathrm{pm}$ (impurity). Atomic number of the impurity is

If the $K_{\mathit{\alpha }}$ radiation of $Mo\mathit{ }\left(Z=42\right)$ has a wavelength array of $0.7 \stackrel{\mathrm{o}}{\mathrm{A}},$ calculate wavelength of the end array corresponding radiation of $Cu\mathit{,}$ i.e., $K_{\mathit{\alpha }}$ for $Cu$ $\left(Z=29\right)$ assuming $b=1:-$

The wavelength of $K_{\alpha }$ line for an element of atomic number $43$ is $\lambda .$ Then what is the wavelength of $K_{\alpha }$ line for an element of atomic number $29$ ?

The wavelength of the $X$-rays produced by an $X$-ray tube is $0.76 \stackrel{\mathrm{o}}{\mathrm{A}}$. What will be the atomic number of anode material?

For characteristic $X$-ray of some material, which of the following must be true?

The $K_{\alpha } \mathrm{X}$-rays arising from a cobalt $(Z=27)$ target have a wavelength of $179 \mathrm{pm}.$ Which of the following is true about the $K_{\alpha } \mathrm{X}$-rays arising from a nickel target $(Z=28)$ ?

The $X$-ray wavelength of $L_{\alpha }$ line of platinum $(Z=78)$ is known to be $1.30 \stackrel{\mathrm{o}}{\mathrm{A}}$. What is the $X$-ray wavelength of $L_{\alpha }$ line of molybdenum $(Z=42)$ ?

What should be the wavelength (in $\stackrel{\circ }{\mathrm{A}}$ ) of X-ray used for getting the first order Bragg reflection at a glancing angle of $14.7°$ for a crystal having a distance of $4 \stackrel{\circ }{\mathrm{A}}$ between its two parallel planes? (Consider$\cos 75.3°=0.25$)

The existence of matter waves was conformed by G.P. Thomson by the phenomena:

In a Coolidge tube experiment for production of $\mathrm{X}-\mathrm{rays}$ , electrons with energy $80 \mathrm{keV}$are incident on the tungsten target . $\mathrm{K}$ shell electrons of tungsten have $-72.5$$\mathrm{keV}$ energy. Choose the correct option regarding  $\mathrm{X}-\mathrm{rays}$being emitted by the tube ?

The wavelength of$10 \mathrm{keV}$ electron beam is $0.1227 \stackrel{\circ }{\mathrm{A}}$. When these waves are diffracted from a metal foil having $\mathrm{d}=0.55 \stackrel{\circ }{\mathrm{A}}$. At angle $\mathrm{\theta }$ first maxima will be present, then what will be the value of $\sin \theta$:

A small aperture is illuminated with parallel beam of light having wavelength $\lambda =942 \mathrm{nm}$. If the first minima is formed at an angular position of $1.5°$ then the size of aperture is