Orbital acceleration of electron is 

1. n2h24π2m2r3   

2. n2h24n2r3

3. 4n2h2π2m2r3 

4. 4n2h24π2m2r3

Subtopic:  Bohr's Model of Atom |
 66%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

Consider the spectral line resulting from transition \(n=2\) to \(n = 1\) in the atoms and ions given below.  The shortest wavelength is given by:
1. hydrogen atom
2. deuterium
3. singly ionised helium
4. doubly ionised lithium

Subtopic:  Spectral Series |
 57%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

An α-particle of energy 5 MeV is scattered through 180° by a fixed uranium nucleus. The distance of closest approach is of the order

1. 10-10 m 

2. 10-13 m 

3. 10-14 m 

4. 10-16 m

Subtopic:  Various Atomic Models |
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

Out of the following which one is not a possible energy for a photon to be emitted by hydrogen atom according to Bohr's atomic model:

1. 13.6 eV

2. 0.65 eV

3. 1.9 eV

4. 11.1 eV

Subtopic:  Bohr's Model of Atom |
 62%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The energy of an electron in an excited hydrogen atom is -3.4 eV.  Its angular momentum will be:
(h = 6.626 × 10-34 J-s)

1. 1.11 × 1034 J s 

2. 1.51 ×10-31 J s

3. 2.11 × 10-34 J s

4. 3.72 × 10-34 J s

Subtopic:  Bohr's Model of Atom |
 70%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

As per the Bohr model, the minimum energy (in eV) required to remove the electron from the ground state of a double ionised lithium ion (Z = 3) is:

1. 1.51

2. 13.6 

3. 40.8

4. 122.4

Subtopic:  Bohr's Model of Atom |
 66%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The wavelength of Ka X-rays produced by an X-ray tube is 0.76 A. Find the atomic number of the anode material of the tube?

1. 41

2. 30

3. 20

4. 10

Subtopic:  X-Ray (OLD NCERT) |
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints

According to Bohr's theory, the moment of momentum of an electron revolving in second orbit of hydrogen atom will be:
1. \(2\pi h\)
2. \(\pi h\) 
3. \(\frac{h}{\pi}\)
4. \(\frac{2h}{\pi}\)

Subtopic:  Bohr's Model of Atom |
 83%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The ionisation energy of a hydrogen atom is 13.6 eV. Following Bohr's theory, what is the energy corresponding to a transition between the 3rd and 4th orbit?
1. 3.40 eV
2. 1.51 eV
3. 0.85 eV 
4. 0.66 eV

Subtopic:  Bohr's Model of Atom |
 72%
From NCERT
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints
Links
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh

The ratio of the energies of the hydrogen atom in its first to second excited states is

1. 14 

2. 49

3. 94

4. 4

Subtopic:  Bohr's Model of Atom |
 61%
To view explanation, please take trial in the course.
NEET 2021 - Achiever Batch - Aryan Raj Singh
Hints