The energy of a photon whose frequency is $10^{12} \text{ MHz}$ is:

$A$ photon,an electron,and a uranium nucleus all have the same wavelength. The one with the most energy is:

The number of photons emitted per second by a bulb of $66 \ W$ power emitting waves of wavelength $600 \ nm$ is . . . . . . . $(h = 6.6 \times 10^{-34} \ J \cdot s)$

$A$ $2\,mW$ laser operates at a wavelength of $500\,nm.$ The number of photons that will be emitted per second is [Given Planck's constant $h = 6.6 \times 10^{-34}\,Js,$ speed of light $c = 3.0 \times 10^8\,m/s$]

$1 \ J$ is equal to how many electron volt?

The energy of a photon with a wavelength of $6.20 \times 10^{-5} \ cm$ is ....... $eV$.