When an $X$-ray photon collides with a proton,its frequency:

Which of the following relations is correct for a photon?

What is the momentum of a photon with a frequency of $10^9 \ Hz$?

The ratio of energies of photons with wavelengths $\lambda_1 = 150 \ nm$ and $\lambda_2 = 300 \ nm$ is:

The momentum of a photon with frequency $1.5 \times 10^{13} \ Hz$ is .......

$A$ lamp of power $942 \ W$ radiates energy uniformly in all directions. The wavelength of radiation is $660 \ nm$. The photon flux on a small screen $5.0 \ m$ from the lamp in units of $\frac{\text{photon}}{m^2 \cdot s}$ is (Take Planck's constant $h = 6.6 \times 10^{-34} \ J \cdot s$ and speed of light $c = 3 \times 10^8 \ m/s$)