Download App

Atoms — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsAtoms1 Mark
Question
For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as 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. A is false and R is also false.
Assertion (A): It is essential that all the lines available in the emission spectrum will not be available in the absorption spectrum.
Reason (R): The spectrum of hydrogen atom is only absorption spectrum
✓

Answer

  1. A is true, but R is false.
Explanation:

Emission transitions can take place between any higher energy level and any energy level below it, while absorption transitions start from the lowest energy level only and may end at any higher energy level. Hence, number of absorptions transitions between two given energy levels is always less than the number of emission transitions between same two levels.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Assertion (A) & Reason (B) MCQ" from Atoms→Atoms — all question types→Physics STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Assertion (A): Light from two coherent sources is reaching the screen. If the path difference at a point on the screen for yellow light is $\frac{3 \lambda}{2}$, then the fringe at that point will be coloured.
Reason (R): Two coherent source always have constant phase relationship.
→
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as 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. A is false and R is also false.
Assertion (A): An ammeter is connected in series in the circuit.
Reason (R): An ammeter is a high resistance galvanometer.
→
Assertion : For a charged particle moving from point P to point Q, the net work done by an electrostatic field on the particle is independent of the path connecting point P to point Q.
Reason : The net work done by a conservative force on an object moving along a closed loop is zero.
→
For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as 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. A is false, and R is also false.
Assertion: Fuse wire must have high resistance and low melting point.
Reason: Fuse is used for small current flow only.
→
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as 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. A is false and R is also false.
Assertion: It is possible to eliminate dispersion by combining two prism of same refracting angles but of different materials.
Reason: The angular dispersion does not depend on refractive index of the material of the prism.
→
Two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from thecodes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Light Emitting Diode $(\text{LED})$ emit spontaneous radiation.
Reason: $\text{LED}$ are forward $-$ biased $p - n$ junction.
→
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as 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. A is false and R is also false.
Assertion: Velocity of light is constant in all media.
Reason: Light is an electromagnetic wave which has constant velocity in all media.
→
Assertion (A): If a proton and electron are moving with same velocity, then wavelength of de-Broglie wave associated with electron is longer than that associated with proton.
Reason (R): The wavelength of de-Broglie wave associated with a moving particle is inversely proportional to its mass.
→
For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as 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. A is false, and R is also false.
Assertion (A): Circuits containing capacitors should be handled cautiously even when there is no current.
Reason (R): The capacitors are very delicate and so quickly breakdown.
→
For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions front the codes (a), (b), (c) and (d) as 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. A is false and R is also false.
Assertion (A): Photosensitivity of a metal is high if its work function is small.
Reason (R): Work function $=\text{h}\upsilon_0,$ where $\upsilon_0$ is the threshold frequency.
→