Entry Test MCQ :: Atomic Spectra
|
|
|
|
|
31. |
UV radiation can be produced by |
A. |
Heating the filament. |
B. |
Electron excitation in the gas. |
C. |
Ionization of atoms. |
D. |
All the above. |
Answer: Option B
Explanation:
|
32. |
What is the velocity of a particle of mass m & de-Broglie wavelength ?? |
Answer: Option A
Explanation:
|
33. |
Wave-like characteristic of electron is demonstrated by |
A. |
Line spectrum of atoms. |
B. |
Production of x-rays. |
C. |
Diffraction by crystalline solids. |
D. |
Photoelectric effect. |
Answer: Option C
Explanation:
|
34. |
Electron cannot exist in the nucleus it is confirmed by observing that |
A. |
It does emit ?-radiation. |
B. |
Its size as compare to proton and neutron is very small. |
C. |
No antiparticle of electron is present. |
D. |
The velocity of electron must be very high according to uncertainty principle. |
Answer: Option D
Explanation:
|
35. |
In normal state of energy the incident high energy photons will be |
A. |
Stimulated. |
B. |
Absorbed. |
C. |
Cause X-ray emission. |
D. |
Cause laser production. |
Answer: Option B
Explanation:
|
36. |
In laser production the state in which more atoms are in the upper state than in the lower one is called |
A. |
Metal stable state. |
B. |
Normal state. |
C. |
Inverted population. |
D. |
All the above. |
Answer: Option C
Explanation:
|
37. |
The metastable state for an atom in laser light is |
A. |
10-4 sec |
B. |
10-5 sec |
C. |
10-3 sec |
D. |
10-8 sec |
Answer: Option C
Explanation:
|
38. |
In He-Ne laser the lasing action is produced by |
A. |
Ne only. |
B. |
He-Ne both |
C. |
Electrons of He. |
D. |
Electrons Ne. |
Answer: Option A
Explanation:
|
39. |
Reflecting mirrors in laser is used to |
A. |
Further stimulation |
B. |
Lasing more |
C. |
For producing more energetic lasers. |
D. |
All |
Answer: Option A
Explanation:
|
40. |
The velocity of laser light is |
A. |
Less than ordinary light. |
B. |
More than ordinary light. |
C. |
Equal to ordinary light. |
D. |
Different for different colours or frequency. |
Answer: Option C
Explanation:
|
Read more:
|
|