How many wavelength are emitted by atomic hydrogen in visible range `(380 nm - 780nm)` ? In the range `50nm to 100 nm`?

Suppose in certine condition only those transition are allowed to hydrogen atoms in which the principal quantum number a changes by 2 (a) Find the smaller wavelength emitted by hydrogen (b) list the wavelength emitted by hydrogen in the visible range (380 nm to 780 nm)

Find the wavelength in a hydrogen spectrum between the range 500nm to 700nm

How many photons are emitted per second by a 5 m W laser source operating at 632.8nm?

White light is incident normally on a glass plate of thickness 0.50 xx 10^(-6) and index of refraction 1.50. Which wavelength in the visible region (400 nm - 700 nm) are strongly reflacted by the plate ?

A parallel beam of white light is incident normally on a water film 1.0 x 10^-4 cm thick. Find the wavelength in the visible range (400 nm-700 nm) which are strongly transmitted by the film Refractive index of water = 1.33.

Three light sources A,B, and C emit equal amount of radiant energy per unit time. The wavelength emitted by the three sources are 450 nm, 555 nm and 700 nm respectively. The brightness sensed by an eye for the sources are X_A, X_B and X_c respectively. Then

A glass surface is coated by an oil film of uniform thickness 1.00xx10^-4 cm. The index of refraction of the oil is 1.25 and that of the glass is 1.50. Find the wavelengths of light in the visible region (400nm-750nm) which are completely transmitted by the oil film under normal incidence.

The velocity of a moving galaxy is 300 kms^(-1) and the apparent change in wavelength of a spectral line emitted from the galaxy is observed as 0.5 nm. Then the actual wavelength of the spectral line is

Electron are emited from an electron gun at almost zero velocity and are accelerated by an electric field E through a distance of 1.0m The electron are now scatteared by an atomic hydrogen sample in ground state what should be the minimum value of E so that red light of wavelength 656.5 nm may be emitted by the hydrogen?

Visible light has wavelengths in the range of 400 nm to 780nm. Calculate the range of energy of the photons of visible light.