Total internal reflexions occur when light traveling through a medium reaches a boundary with a lower refractive index and is completely reflected back into the medium.

Total internal reflexion is a phenomenon that occurs when light traveling in a medium with a higher refractive index is reflected back into the same medium instead of being transmitted into a medium with a lower refractive index.

I saw a group of ice scooters racing on the frozen lake.

I rented an ice scooter for the day.

After years of unemployment, he finally found a job and was brought in from the cold.

We all agreed in one voice to support the new proposal.

The Marquesas Islands are a group of volcanic islands in French Polynesia.

Ice swimmers brave the freezing waters to compete in winter swimming events.

He is an avid ice swimmer and participates in competitions regularly.

They are mucking in to help clean up the park.