Question 3 . Thank you . 4
(A)
(C)
4
2
2
3
3
4
(D)
B
4
c
3
2
3
2
2.
3.
4.
5
6.
7.
8.
When Z is doubled in an atom, which of the following statements are consistent With Bohr's theory?
(A) Energy of a state is doubled
(B) R s bf an orbit is doubled.
( elocity Of electron in an orbit is doubled.
(D) Energy of a state is halved
A photon of 300 nm is absorbed by a gas and then emits two photons. Pne photon has a wavelength 496 nm
then the wavelength of second photon in nm is :
(B) 859
(C) 959
(A) 759
(D) 659
If the total energy Of an electron in hydrogen like atom in an excited state is —3.4 eV, then the
de-Broglie wavelength of the electron is :
150
3.4
150
(B)
6.8
150
(C)
nm
3.4
150
(D)
nm
6.8
An electron, a Gt@ånd an alpha particle have kinetic energies of 16E, 4E and E respectivei . What is the
quanti tive order of their de-Broglie wavelengths ?
-1-01
9
When an excited hydrogen atom returned to its ground state, some visible quanta were observed alongwith •
other quanta . Which of the following transitions must have occurred?
The radii of two of the first four Bohr's orbits of the hydrogen atom are in the ratio 1 : 4 the energy difference
between them may be :
(A) Either 12.09 ev or 10.2 ev
(C) Either 13.6 ev or 3.4 ev
Either 2.55 eV or 10.2 eV
(D) Either 3.4 eV or 0.85 eV
A proton and an a-particle Åre accelerated through the same potential difference from rest. Then the ratio of
thefr Broglie wavelength is :
