According to Bohr's theory, the expressions for the kinetic and potential energy of an electron revolving in an orbit is given respectively by
(a)$+\frac{{\mathrm{e}}^{2}}{8{\mathrm{\pi \epsilon }}_{0}\mathrm{r}}$ and  $-\frac{{\mathrm{e}}^{2}}{4{\mathrm{\pi \epsilon }}_{0}\mathrm{r}}$            (b) $+\frac{8{\mathrm{\pi \epsilon }}_{0}{\mathrm{e}}^{2}}{\mathrm{r}}$ and $-\frac{4{\mathrm{\pi \epsilon }}_{0}{\mathrm{e}}^{2}}{\mathrm{r}}$
(c) $-\frac{{\mathrm{e}}^{2}}{8{\mathrm{\pi \epsilon }}_{0}\mathrm{r}}$ and $-\frac{{\mathrm{e}}^{2}}{4{\mathrm{\pi \epsilon }}_{0}\mathrm{r}}$            (d) $+\frac{{\mathrm{e}}^{2}}{8{\mathrm{\pi \epsilon }}_{0}\mathrm{r}}$ and $+\frac{{\mathrm{e}}^{2}}{4{\mathrm{\pi \epsilon }}_{0}\mathrm{r}}$

Concept Questions :-

Bohr's model of atom
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The minimum energy required to excite a hydrogen atom from its ground state is

(a) 13.6 eV                   (b) -13.6 eV
(c) 3.4 eV                     (d) 10.2 eV

Concept Questions :-

Bohr's model of atom
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Ratio of the wavelengths of first line of Lyman series and first line of Balmer series is
(a) 1: 3                  (b) 27 : 5
(c) 5 : 27               (d) 4 : 9

Concept Questions :-

Spectral series
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Difficulty Level:

The velocity of an electron in the second orbit of sodium atom (atomic number = 11) is v. The velocity of an electron in its fifth orbit will be
(a) v            (b) $\frac{22}{5}v$
(c) $\frac{5}{2}\mathrm{v}$        (d) $\frac{2}{5}\mathrm{v}$

Concept Questions :-

Bohr's model of atom
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The absorption transitions between the first and the fourth energy states of hydrogen atom are 3. The emission transitions between these states will be
(a) 3              (b) 4
(c) 5              (d) 6

Concept Questions :-

Spectral series
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Difficulty Level:

The ratio of longest wavelength and the shortest wavelength observed in the five spectral series of emission spectrum of hydrogen is
(a) $\frac{4}{3}$             (b) $\frac{525}{376}$
(c) 25             (d) $\frac{900}{11}$

Concept Questions :-

Spectral series
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Difficulty Level:

In Bohr's model of hydrogen atom, let PE represents potential energy and TE the total energy. In going to a higher level

(a) PE decreases, TE increases

(b) PE increases, TE increases

(c) PE decreases, TE decreases

(d) PE increases, TE decreases

Concept Questions :-

Bohr's model of atom
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

According to Bohr's model, the radius of the second orbit of helium atom is
(a) 0.53 Å             (b) 1.06 Å
(c) 2.12 Å             (d) 0.265 Å

Concept Questions :-

Bohr's model of atom
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The fact that photons carry energy was established by

(a) Doppler's effect               (b) Compton's effect
(c) Bohr's theory                   (d) Diffraction of light

Concept Questions :-

Bohr's model of atom
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

An ionic atom equivalent to hydrogen atom has wavelength equal to 1/4 of the wavelengths of hydrogen lines. The ion will be
(a) ${\mathrm{He}}^{+}$         (b) ${\mathrm{Li}}^{++}$
(c) ${\mathrm{Ne}}^{9+}$        (d) ${\mathrm{Na}}^{10+}$

Concept Questions :-

Spectral series