$A$: Thomson's atomic model is known as the plum pudding model.
$R$: The atom is considered as a positively charged sphere in which electrons are embedded.

Which of the following statements are correct,if the threshold frequency of caesium is $5.16 \times 10^{14} \ Hz$?
$A.$ When $Cs$ is placed inside a vacuum chamber with an ammeter connected to it and yellow light is focused on $Cs$,the ammeter shows the presence of current.
$B.$ When the brightness of the yellow light is dimmed,the value of the current in the ammeter is reduced.
$C.$ When a red light is used instead of the yellow light,the current produced is higher with respect to the yellow light.
$D.$ When a blue light is used,the ammeter shows the formation of current.
$E.$ When a white light is used,the ammeter shows the formation of current.
Choose the correct answer from the options given below:

If the energy of a photon is $14 \, eV$ and it interacts with a hydrogen atom,which of the following is correct?

In a hydrogen atom,the energy of an $e^-$ in an orbital is given by $E = \frac{-constant}{n^2} \ (kJ \ mol^{-1})$. Which of the following properties is constant according to the given equation?

Calculate the wavenumber of the photon emitted during transition from the orbit of $n=2$ to $n=1$ in a hydrogen atom. $[R_H = 109677 \ cm^{-1}]$ (in $cm^{-1}$)

Which transition in a $H$ atom has the same wavelength as the transition from $n = 4$ to $n = 2$ in a $He^{+}$ ion?