Imagine an atom made of a proton and a hypothetical particle of double the mass of the electron but having the same charge as the electron. Apply the Bohr atom model and consider all possible transitions of this hypothetical particle to the first excited level. The longest wavelength photon that will be emitted has wavelength [given in terms of Rydberg constant R for the hydrogen atom ] equal to
1.
2.
3.
4.
The following diagram indicated the energy levels of a certain atom when the system moves from 4E level to E. A photon of wavelength is emitted. The wavelength of photon produced during its transition from level to E is . The ratio will be
1.
2.
3.
4.
If the series limit of Lyman series for Hydrogen atom is equal to the series limit of Balmer series for a hydrogen- like atom, then atomic number of this hydrogen like atom will be -
1. 1
2. 2
3. 3
4. 4
An electron of the kinetic energy 10 eV collides with a hydrogen atom in the 1st excited state. Assuming loss of kinetic energy in the collision to be quantized which of the following statements is correct ?
1. The collision may be perfectly inelastic
2. The collision may be inelastic
3. The collision may be elastic
4. The collision must be inelastic
A monochromatic radiation of wavelength is incident on a sample containing He+. As a result the Helium sample starts radiating. A part of his radiation is allowed to pass through a sample of atomic hydrogen gas in ground state. It is noticed that the hydrogen sample has started emitting electrons whose maximum kinetic energy is 37.4 eV. (hc = 12400 eV ). Then is
1. 275
2. 243
3. 656
4. 386
In a sample of hydrogen like atoms of all of which are in ground state, a photon beam containing photons of various energies is passed. In absorption spectrum five dark lines are observed. The number of bright lines in the emission spectrum will be (assume that all transitions takes place)
1. 5
2. 10
3. 15
4. None of these
What is the angular momentum of an electron in Bohr's hydrogen atom whose energy is -0.544 eV?
1.
2.
3.
4.
The energy level diagram for an hydrogen like atom is shown in the figure. The radius of its first Bohr orbit is
1. 0.265
2. 0.53
3. 0.132
4. None of these
Consider a hydrogen like whose energy in nth excited state is given by when this excited atom makes a transition from excited state to ground state, most energetic photons have energy and least energetic photons have energy . The atomic number of atom is
1. 2
2. 5
3. 4
4. None of these
If we assume that penetrating power of any radiation/ particle is inversely proportional to its de-Broglie wavelength of the particle then :
1. A proton and an -particle after getting accelerated through same potential difference will have equal penetrating power.
2. Penetrating power of -particle will be greater than that of proton which have been accelerated by same potential difference
3. Proton's penetrating power will be less than penetrating power of an electron which has been accelerated by the same potential difference
4. Penetrating powers cannot be compared as all these are particles having no wavelength or wave nature
If first excitation potential of a hydrogen like atom is V electron volt, then the ionization energy of this atom will be :
1. V electron volt
2. electron volt
3. electron volt
4. cannot be calculated by given information
In the figure six lines of emission spectrum are shown. Which of them will be absent in the absorption spectrum
1. 1,2,3
2. 1,4,6
3. 4,5,6
4. 1,2,3,4,5,6
The ionisation potential of H-atom is 13.6 V. When it is excited from ground state by monochromatic radiations of 970.6 , the number of emission lines will be (according to Bohr's theory)
1. 10
2. 8
3. 6
4. 4