138k views
5 votes
show that the first order and second order spectra from a diffraction grating will never overlap when the grating is used for studying a light beam containing wavelength components from 400 to 700 nm.

User Andy Lynch
by
7.7k points

1 Answer

5 votes

The first and second-order spectra from a diffraction grating will not overlap when studying a light beam with wavelength components from 400 to 700 nm due to the consistent separation between adjacent orders, ensuring non-overlapping spectral regions.

The separation between adjacent orders in a diffraction grating is determined by the grating equation: mλ=dsin(θ), where m is the order, λ is the wavelength, d is the grating spacing, and θ is the angle of diffraction. For a given wavelength, the orders are discrete and well-defined.

In the context of studying a light beam containing wavelength components from 400 to 700 nm, the first-order spectrum corresponds to the wavelengths diffracted at a certain angle, and the second-order spectrum corresponds to wavelengths diffracted at twice that angle. The key point is that these angles are distinct for different orders.

Considering the range of wavelengths (400 to 700 nm), the orders will be separated by a consistent angular spacing, preventing overlap between the first and second-order spectra. This non-overlapping nature ensures that each order represents a unique spectral region, facilitating the precise analysis of the different wavelength components in the light beam using a diffraction grating.

User Thurgood
by
7.7k points