What is total internal reflection?

What must happen for total internal reflection to occur?

What is the critical angle?

How do you calculate the critical angle?

How do you calculate the critical angle if light is passing from x medium into air?

What material gives the smallest critical angle?

What can total internal reflection be used for?

How is total internal reflection used in optical fibres?

What are optical fibres used for?

What two types of optical fibres are used in telecommunications?