Understanding Total Internal Reflection and Critical Angle

What happens to light when it moves from a medium with a higher refractive index to a lower one?

• It bends towards the normal.

• It bends away from the normal.

• It continues in a straight line.

• It reflects back into the original medium.

What is the critical angle?

• The angle at which light travels in a straight line.

• The angle at which light refracts into the second medium.

• The angle at which light remains in the original medium.

• The angle at which light reflects back into the original medium.

What occurs when the angle of incidence exceeds the critical angle?

• Light reflects back into the original medium.

• Light refracts into the second medium.

• Light is absorbed by the boundary.

• Light travels in a straight line.

Which law is used to derive the formula for the critical angle?

• Ohm's Law

• Newton's Law

• Snell's Law

• Hooke's Law

In the context of Snell's Law, what is the angle of refraction when the angle of incidence is the critical angle?

• 180 degrees

• 90 degrees

• 45 degrees

• 0 degrees

What is the sine of 90 degrees?

• 1

• Undefined

• 0.5

• 0

How is the critical angle calculated for a medium with a refractive index of 1.5?

• Inverse sine of 1/1.5

• Inverse cosine of 1/1.5

• Inverse cosine of 1.5

• Inverse sine of 1.5

What is the approximate value of the critical angle for a refractive index of 1.5?

• 30 degrees

• 42 degrees

• 60 degrees

• 90 degrees

What assumption is made about the second refractive index in the derivation of the critical angle formula?

• It is greater than 1.

• It is equal to 0.

• It is less than 1.

• It is equal to 1.

What should you do if you have questions about the content?

• Drop a comment.

• Rewatch the video.

• Search online.

• Ignore them.