IB DP Physics: HL复习笔记9.4.3 Resolvance of Diffraction Gratings
Resolvance of Diffraction Gratings
- In order to know if a diffraction grating is able to resolve two wavelengths, the resolving power of the diffraction grating must be found
- This is based on the Rayleigh criterion as applied to diffraction gratings and their output
- The resolving power, R, of a diffraction grating is given by:
Worked ExampleA student is using a diffraction grating to resolve two emission wavelengths from calcium in the 3rd order of the spectrum. These wavelengths are 164.99 nm and 165.20 nm.
Determine the minimum number of lines per mm needed if a beam of width 0.25 mm is incident upon the diffraction grating.
-
-
Order of diffraction, m = 3
-
Wavelength, λ1 = 164.99 nm
-
Wavelength, λ2 = 165.20 nm
-
Beam width = 0.25 mm
-
-
- The value of the incident wavelength, λ, can be determined from the mean of the two wavelengths:
- The value of the incident wavelength, λ, can be determined from the mean of the two wavelengths:
Exam Tip
In the worked example, the answer may look as though it has been rounded incorrectly but we are looking for the actual number of lines here, not fractions of lines
Rounding down to 1048 would leave the grating nearly half a line short, which can't happen, so always round up to the nearest whole number
转载自savemyexams
以上就是关于【IB DP Physics: HL复习笔记9.4.3 Resolvance of Diffraction Gratings】的解答，如需了解学校/赛事/课程动态，可至翰林教育官网获取更多信息。
往期文章阅读推荐：
翰林独家 | 经济学竞赛核心精讲，一册打通NEC/IEO/USAEBO！
2026 AMC10/12美国数学竞赛新赛季！【翰林教育 × 清华大学出版社】独家教材全面发售！
翰林AMC8视频课重磅上线！
国际竞赛真题资源免费领取
