In optics, refraction occurs when waves travel from a medium with a given refractive index to a medium with another at an angle. At the boundary between the media, the wave's phase velocity is altered, usually causing a change in direction.Its wavelength increases or decreases but its frequency remains constant.y measuring the angle of incidence and angle of refraction of the light beam, the refractive index n can be determined. Refractive index of materials varies with the frequency of radiated light. This results in a slightly different refractive index for each color.
If you suspect Medicare fraud please report it by phone at 1-800-447-8477 (1-800-HHSTIPS), or E-Mail at HHSTips@oig.hhs.gov. To report Medicaid fraud in North Carolina, call the North Carolina Medicaid Investigations Division at 919-881-2320.
Protect yourself and Medicare against fraud by reviewing your Medicare claims for errors, looking for other types of fraud, and reporting anything suspicious to Medicare. 1  Learn how to spot fraud. 2  Learn how to report fraud. 3  Learn more tips to help prevent Medicare fraud.