In the spectrum of hydrogen, the ratio of the longest wavelength in the Lyman series to the longest wavelength in the Balmer series is
Options
(a) (27/5) (b) (5/27) (c) (4/9) (d) (9/4)
A nucleus of uranium decays at rest into nuclei of thrrium and helium. Then
Options
(a) The helium nucleus has more momentum than the thorium nuclues (b) The helium nucleus has less kinetic […]
If radius of the ₁₃Al²⁷ nucleus is taken to be Rᴀı, then the radius of ₅₃Te¹²⁵ nucleus is nearly
Options
(a) (53/13)¹⁄₃ Rᴀı (b) 5/3Rᴀı (c) 3/5Rᴀı (d) (13/53)¹⁄₃ Rᴀı
Correct Answer:
5/3Rᴀı
Explanation: […]
Consider 3rd orbit of He⁺(helium), using non-relativistic approach, the speed of electron in this orbit will be (given K=9×10⁹ constant, Z=2 and h=6.6×10⁻³⁴ J-s)
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(a) 2.92×10⁶ ms⁻¹ (b) 1.46×10⁶ ms⁻¹ (c) 0.73×10⁶ […]
The binding energy per nucleon of ₃⁷Li and ₂⁴He nuclei are 5.60 MeV and 7.06MeV, respectively. In the nuclear reaction ₃⁷Li+₁¹H→ ₂⁴He+ ₂⁴He+Q, the value of energy Q released is
Options
(a) 19.6 […]
Hydrogen atom in ground state is excited by a monochrmatic radiation of λ=975 Å. Number of spectral lines in the resulting spectrum emitted will be
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(a) 3 (b) 2 (c) 6 (d) […]
A radio isotope X with a half life 1.4 x 10⁹ years decays to Y which is stable. A sample of the rock from a cave was found to contain X and Y in the […]
The nuclear radius of a certain nucleus is 7.2 fm and it has a charge of 1.28×10⁻¹⁷ C. The number of neutrons inside the nucleus is
Options
(a) 136 (b) 142 (c) 140 […]
The most stable particle in Baryon group is
Options
(a) Proton (b) Lamda-particle (c) Neutron (d) Omega-particle
Correct Answer:
Proton
Explanation:
The proton is the most stable in the Baryon group.
On bombarding U²³⁵ by slow neutron, 200 MeV energy is released. If the power output of atomic reactor is 1.6 MW, then the rate of fission will be
Options
(a) 8×10¹⁶/s (b) 20×10¹⁶/s (c) […]
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