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

A hydrogen - like atom (described by the Bohr model) is observed to emit six wavelength , originating from all possible transitions between - 0.85 eV and -0.544 eV (including both these values ) (a) Find the atomic number of the atom (b) Calculate the smallest wavelength emitted in these transitions . (Take hc = 1240 eV - nm , ground state energy of hydrogen atom = 13.6 eV)

A black body is at a temperature of 2800K The energy of radiation emitted by this object with wavelength between 499nm and 500 nm is U_(1) between 999nm and 1000nm is U_(2) and between 1499 nm and 1500 nm is U_(3) .The Wien's constant b =2.80 xx 10^(6) nm K Then .

The wavelength range of the visible spectrum extends from vloler (400nm) to red (750 nm) Express these wavelength in frequency (Hz )

There are two sources of light,each emitting with a power of 100W.One emits X-rays of wavelength 1 nm and the other visible light at 500 nm.Find the ratio of number of photons of X-rays to the photon of visible light of the given wavelength?

The wavelength of first line of Balmer series is 656 nm . Calculate the wave length of second line of this series. (Note : first line means n_(3) to n_(2) and second line means n_(4) to n_(2)

White light consisting of wavelengths 380 nm le lambda le 750 nm is incident on a lead surface. For which one of the following ranges of wavelength will photoelectrons be emitted from the lead surface that has a work function W_(0) = 6.63 xx 10^(-29) J ?

The largest wavelength in the ultraviolet region of the hydrogen spectrum is 122 nm. The smallest wavelength in the infrared region of the hydrogen spectrum (to the nearest integer) is

What is the order of radiation pressure of visible light in Nm^(-2) ?

The wavelength of light in the visible region is about 390 nm for violet colour, about 550 nm (average wavelength) for yellowgreen colour and about 760 nm for red colour. (a) What are the energies of photons in (eV) at the (i) violet end, (ii) average wavelength, yellow-green colour, and (iii) red end of the visible spectrum? ("Take h "= 6.63xx10^(-34)" J s and 1 eV" = 1.6xx10^(-19)J.) (b) From which of the photosensitive materials with work functions listed in Table 11.1 and using the results of (i), (ii) and (iii) of (a), can you build a photoelectric device that operates with visible light?