A monochromatic laser beam with a wavelength of 720 nm illum…

A monochromatic laser beam with a wavelength of 720 nm illuminates a narrow slit with a width of 1 ×10-6 m. The resulting diffraction pattern is formed on a screen that is located at 1 m from the slit. What is the width of the pattern’s central maximum (measured in m)?

A 500-nm-wavelength beam of light illuminates a soap film wi…

A 500-nm-wavelength beam of light illuminates a soap film with air on both sides and an index of refraction 1.33. If the beam of light is incident normally on the film, what is the minimum thickness of the film to make the reflected light enhanced in brightness (constructive interference)? Express the answer in nanometers, nm.