Math model of metal heating under action by laser beam章节测试课后答案2024春

第三章测试

1.The Doppler broadening of the CO2 spectral line is 53 MHz, and the extreme value of the spectral line function corresponding to the central frequency is （ ）。
A:1.7× 10-9s B:1.7× 109Hz C:1.7× 10Hz D:1.7× 10-9Hz
答案:A
2.Q-modulated lasers can usually obtain （ ） magnitude short pulses.
A:fs B:μs C:ms D:ns
答案:D
3.Ruby laser is a typical （ ） system。
A:Four-energy level B:Multi-energy level C:Three energy level D:Dienergy level
答案:C
4.Doppler broadening has occurred in （ ） media.
A:Solids B:liquids C:liquids D:Isolates
答案:B
5.He-Ne lasers belong to the typical （ ） system .
A:four energy levels, B:multi-energy level C:two energy levels D:three energy levels
答案:A
6.The characteristics of laser cavity oscillation mode are（ ）。
A:The divergence angle of the laser beam for each mode. B:The electromagnetic field theory of the mode. C:The simple harmonic frequency of the mode. D:The relative power loss experienced by the mode during one round trip in the cavity.
答案:ABCD
7.For the same medium, the small signal gain coefficient varies with （ ）。
A:particle number density B:Spectral line width C:Excitation power D:Spontaneous radiation chance
答案:C
8.Natural broadening is caused by （ ）.
A:collisions of particles B:the Doppler effect C:excited states have a certain lifetime D:vibration of particles
答案:C
9.The resonant frequency of the longitudinal mode of the resonant cavity is （ ）。
A: B: C: D:
答案:B
10.Symmetric confocal cavity base mode light waist for （ ）。
A: B: C: D:
答案:C