Yes, you can rearrange the equations E = hc/λ (where E is the energy of a photon, h is the Planck constant, c is the speed of light, and λ is the wavelength of the photon) and E = mc^2 (where E is the energy of an object, m is the mass of the object, and c is the speed of light) to find the mass of a photon.
Let's start with the equation E = hc/λ and solve for λ:
λ = hc/E
Now, substitute this expression for λ into the equation E = mc^2:
hc/E = mc^2
Simplifying the equation further:
h = mc
Dividing both sides of the equation by c:
h/c = m
Therefore, the equation reveals that the mass of a photon (m) can be expressed as m = h/c. It shows that the mass of a photon is proportional to the Planck constant (h) divided by the speed of light (c). However, it's important to note that the mass of a photon is extremely small, and for practical purposes, it is often considered massless.