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

What is the speed of all types of electromagnetic radiation in a vacuum? What is it called?

When electromagnetic radiation of wavelength $300 \, nm$ falls on the surface of a metal,electrons are emitted with the kinetic energy of $1.68 \times 10^5 \, J \, mol^{-1}$. What is the minimum energy needed to remove an electron from the metal? $(h = 6.626 \times 10^{-34} \, J \, s, c = 3 \times 10^8 \, m \, s^{-1}, N_A = 6.022 \times 10^{23} \, mol^{-1})$

$a$,$b$,$c$,$d$ are electromagnetic radiations. Frequencies of $a$,$b$ are $3 \times 10^{15} \ Hz$,$2 \times 10^{14} \ Hz$,respectively,whereas wavelengths of $c$,$d$ are $400 \ nm$,$750 \ nm$,respectively. The increasing order of their energies is

Chlorophyll in green plants absorbs light of frequency $4.620 \times 10^{14} \ Hz$. Find the wavelength and the region in the electromagnetic spectrum.

If $p$ is the momentum of the fastest electron ejected from a metal surface after the irradiation of light having wavelength $\lambda$,then for $1.5 \ p$ momentum of the photoelectron,the wavelength of the light should be: (Assume kinetic energy of ejected photoelectron to be very high in comparison to work function)