| 1 |
Laser is a beam of light which is |
- A. Monochromatic
- B. Coherent
- C. Unidirectional
- D. All of these
|
| 2 |
The series in visible region is: |
- A. Balmer series
- B. Pfund series
- C. Paschen series
- D. None of above
|
| 3 |
Radius of first orbit of an atom is r1= 0.053 nm, Radius of second orbit r2 will be. |
- A. 0.106 nm
- B. 0.212 nm
- C. 0.053 nm
- D. 0.53 x 10<sup><a href="null">-10</a></sup> nm
|
| 4 |
The X-rays diffraction with crystal was first studied by |
- A. W.H Bragg
- B. W.L. Bragg
- C. Michelson
- D. None of these
|
| 5 |
In Helium Neon laser, discharge tube is filled with Neon gas. |
- A. 10%
- B. 15%
- C. 85%
- D. 90%
|
| 6 |
The Balmer series is obtained when all the transition of electrons terminate on |
- A. 1<sup>st</sup> orbit
- B. 2nd orbit
- C. 3rd orbit
- D. 4th orbit
|
| 7 |
Balmer Empirical formula explains the electromagnetic radiation of any excited atom in terms of their. |
- A. Energy
- B. Mass
- C. Wave length
- D. Momentum
|
| 8 |
Reflecting mirrors in laser is used to |
- A. Further stimulation
- B. For producing more energetic lasers
- C. Both (a) and (b)
- D. None of these
|
| 9 |
A° is the unit of: |
- A. Energy
- B. Length
- C. Nuclear energy
- D. Work
|
| 10 |
The idea of laser device was first introduced by C.H. Towners and Authers Schowlan is |
- A. 1972
- B. 1965
- C. 1958
- D. 1913
|
