Advertisements
Advertisements
प्रश्न
The ground state energy of hydrogen atoms is -13.6 eV. The photon emitted during the transition of electron from n = 3 to n = 1 unknown work function. The photoelectrons are emitted from the material with a maximum kinetic energy of 9 eV. Calculate the threshold wavelength of the material used.
Advertisements
उत्तर
For a transition from n = 3 to n = 1 state, the energy of the emitted photon,
hv = E2 – E1 = `13.6[1/1^2 - 1/3^2]` eV = 12.1 eV.
From Einstein’s photoelectric equation,
hv + Kmax + W0
∴ W0 = hv – Kmax = 12.1 – 9 = 3.1 eV
Threshold wavelength,
λth = `("hc")/"W"_0`
= `(6.62 xx 10^-34 xx 3 xx 10^8)/(3.1 xx 1.6 xx 10^-19)`
= 4 × 10–7m
APPEARS IN
संबंधित प्रश्न
Using Bohr's postulates of the atomic model, derive the expression for radius of nth electron orbit. Hence obtain the expression for Bohr's radius.
What is the maximum number of emission lines when the excited electron of an H atom in n = 6 drops to the ground state?
In accordance with the Bohr’s model, find the quantum number that characterises the earth’s revolution around the sun in an orbit of radius 1.5 × 1011 m with orbital speed 3 × 104 m/s. (Mass of earth = 6.0 × 1024 kg)
When a photon stimulates the emission of another photon, the two photons have
(a) same energy
(b) same direction
(c) same phase
(d) same wavelength
A beam of light having wavelengths distributed uniformly between 450 nm to 550 nm passes through a sample of hydrogen gas. Which wavelength will have the least intensity in the transmitted beam?
The energy associated with the first orbit of He+ is ____________ J.
Consider two different hydrogen atoms. The electron in each atom is in an excited state. Is it possible for the electrons to have different energies but same orbital angular momentum according to the Bohr model? Justify your answer.
The wavelength of the first time line of Ballmer series is 6563 A°. The Rydberg constant for hydrogen is about:-
If a proton had a radius R and the charge was uniformly distributed, calculate using Bohr theory, the ground state energy of a H-atom when (i) R = 0.1 Å, and (ii) R = 10 Å.
Hydrogen atom from excited state comes to the ground state by emitting a photon of wavelength λ. If R is the Rydberg constant then the principal quantum number n of the excited state is ______.
