A diffraction grating has 600 lines per millimetre. Light of wavelength 550 nm is incident normally. At what angle is the first-order maximum?
Answer and explanation
Correct answer: B. 19.3 degrees
- Step 1: Slit spacing m. Step 2. gives . Step 3. . Answer: 19.3 degrees. Why not the others: 33.0 degrees treats as the angle; 9.5 degrees uses in the denominator; 70.7 degrees is .
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