An electron having de-Broglie wavelength $\lambda$ is incident on a target in a X-ray tube. Cut-off wavelength of emitted $X$-ray is :
$0$
$\frac{h c}{m c}$
$\frac{2 m^{2} c^{2} \lambda^{2}}{h^{2}}$
$\frac{2 m c \lambda^{2}}{h}$
In Rutherford scattering experiment, what will be the correct angle for $\alpha $ scattering for an impact parameter $b = 0$.....$^o$
Assertion $(A)$ : The magnetic moment $(\mu)$ of an electron revolving around the nucleus decreases with increasing principle quantum number $(n)$.
Reason $(R)$ : Magnetic moment of the revolving electron, $\mu \propto n$.
The number of completely filled shells for the element ${ }_{16} S ^{32}$ is
How many energy rays of $\alpha -$ particles emitted from $_{83}^{214}Bi$ were taken?
In an atom for the electron to revolve around the nucleus, the necessary centripetal force is obtained from the following force exerted by the nucleus on the electron