What is the ratio of velocity of light of wavelengths `4000 oversetcircA` and `8000 oversetcircA` in vacuum?

What is the ratio of velocities of light rays of wavelength 5,000 overset @ A and 7,000 overset @A in vacuum?

Give the ratio of velocities of light rays of wave length 4000A^@ and 6000^@ in vacuum.

Find the momentum of a photon of wavelength 0.01 oversetcircA .

Give the ratio of velocities of light waves of wavelengths 4000 lambda and 8000 lambda in vacumm.

Give the ratio of velocities of light rays of equal wavelength in vacuum.

What is the numerical ratio of velocity to speed of an object?

The value of velocity of light in vacuum is:

What is the number of photon of light with a wvelengthof 4000 pm that provide 1 J of energy ?