How many orders of spectra are possible with a grating of 15000 lines per inch?

Answer 1

To determine the number of orders of spectra possible with a grating of 15,000 lines per inch, we first convert the lines per inch to lines per meter, resulting in approximately 5905 lines per meter. The maximum order ( m ) of the spectrum can be calculated using the formula ( m \leq \frac{d}{\lambda} ), where ( d ) is the grating spacing (the inverse of the number of lines per meter) and ( \lambda ) is the wavelength of light. For visible light (approximately ( 400 ) to ( 700 ) nm), this results in a maximum of about 5 to 6 orders of spectra being observable, depending on the specific wavelength used.