The frequency of a wave of light is $12 \times 10^{14} \ s^{-1}$. The wave number associated with this light is

In the hydrogen spectrum,the different lines of the Lyman series are present in the:

Calculate $(a)$ wavenumber and $(b)$ frequency of yellow radiation having wavelength $5800 \, \mathring{A}$.

In the visible spectrum,which color,violet or red,undergoes greater refraction? Why?

The frequency of an electromagnetic radiation is $2 \times 10^6 \ Hz$. What is its wavelength in metres? (Velocity of light $= 3 \times 10^8 \ m \ s^{-1}$)

Which of the following statements is correct about the photoelectric effect?
$1$. The number of electrons ejected from a metal surface is inversely proportional to the intensity of light.
$2$. Below the threshold frequency,the photoelectric effect can be observed.
$3$. At a frequency higher than the threshold frequency,the ejected electrons have a certain kinetic energy.
$4$. At a frequency higher than the threshold frequency,the electron is still on the metal surface.