Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R): 
 
Assertion (A): LASER is used to measure distant objects as moon.
Reason (R): They are highly coherent sources of light.

In the light of the above statements choose the correct answer from the options given below:
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
.

Subtopic:  Spectral Series |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given below are two statements: 
Assertion (A): Bohr had to postulate that the electrons in stationary orbits around the nucleus do not radiate.
Reason (R): According to classical physics all accelerating electrons radiate.
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  Bohr's Model of Atom |
 52%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R): 
 
Assertion (A): In He-Ne laser, population inversion takes place between energy levels of neon atoms.
Reason (R): Helium atoms have a meta-stable energy level.

In the light of the above statements choose the correct answer from the options given below:
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Spectral Series |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R): 
 
Assertion (A): A hydrogen atom at the ground state cannot absorb a photon of energy 10 eV.
Reason (R): First excitation energy of the hydrogen atom is 10.2 eV. The hydrogen atom absorbs only those photons which provide it the excitation energy.

In the light of the above statements choose the correct answer from the options given below:
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Bohr's Model of Atom |
 77%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R): 
 
Assertion (A): Magnetic moment associated with an electron in hydrogen atom is quantized.
Reason (R): Magnetic moment associated with the electron is an integral multiple of Bohr's magneton but is independent of atomic number.

In the light of the above statements choose the correct answer from the options given below:
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Bohr's Model of Atom |
 74%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R): 
 
Assertion (A): Rydberg's constant does not vary with the mass number of a given element.
Reason (R): The reduced mass of the electron is dependent on the mass of the nucleus only.

In the light of the above statements choose the correct answer from the options given below:
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
 
 
Subtopic:  Bohr's Model of Atom |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

Given below are two statements: 
Statement I: The time period of revolution of an electron in its \(n^\text{th}\) Bohr orbit in an atom is directly proportional to \(n^3.\)
Statement II: The K.E of an electron in its \(n^\text{th}\) Bohr orbit in an atom is directly proportional to \(n.\)
1. Statement I is incorrect and Statement II is correct.
2. Both Statement I and Statement II are correct.
3. Both Statement I and Statement II are incorrect.
4. Statement I is correct and Statement II is incorrect.
Subtopic:  Bohr's Model of Atom |
 80%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given below are two statements:
Assertion (A): The Balmer series lies in the visible region of the electromagnetic spectrum.
Reason (R): \(\frac{1}{\lambda}={R}\left[\frac{1}{2^{2}}-\frac{1}{n^{2}}\right], \text { where } n=3,4,5.\)
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.


 
Subtopic:  Spectral Series |
 64%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Given below are two statements:
Assertion (A): The hydrogen atom consists of only one electron but its emission spectrum has many lines.
Reason (R): Only Lyman series is found in the absorption spectrum of hydrogen atoms whereas in the emission spectrum, all the series are found.
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.


 
Subtopic:  Spectral Series |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

Given below are two statements: 
Assertion (A): The positively charged nucleus of an atom has a radius of almost \(10^{-15}~\text{m}\).
Reason (R): I\(\alpha\)-particle scattering experiment, the distance of the closest approach for \(\alpha\)-particle is \(\approx 10^{-15}~\text m\).
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  Various Atomic Models |
 58%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch