Snell's Law

Front

What is Snell's Law?

Back

Snell's Law describes how light rays change direction when they pass from one medium to another. It is mathematically expressed as n1 * sin(θ1) = n2 * sin(θ2), where n is the index of refraction and θ is the angle of incidence or refraction.

Front

What is the index of refraction?

Back

The index of refraction (n) is a dimensionless number that describes how fast light travels in a medium compared to its speed in a vacuum. It is calculated as n = c/v, where c is the speed of light in a vacuum and v is the speed of light in the medium.

Front

If light travels from air (n=1) to water (n=1.33), what happens to its speed?

Back

The speed of light decreases when it enters water from air because water has a higher index of refraction.

Front

What is the angle of incidence?

Back

The angle of incidence is the angle between the incident ray and the normal (a line perpendicular to the surface) at the point of incidence.

Front

What is the angle of refraction?

Back

The angle of refraction is the angle between the refracted ray and the normal at the point of refraction.

Front

How does the angle of incidence relate to the angle of reflection?

Back

According to the law of reflection, the angle of incidence is equal to the angle of reflection.

Front

What happens to light when it passes from a less dense medium to a more dense medium?

Back

When light passes from a less dense medium (like air) to a more dense medium (like glass), it bends towards the normal.

Front

What is total internal reflection?

Back

Total internal reflection occurs when light attempts to move from a denser medium to a less dense medium at an angle greater than the critical angle, causing it to reflect entirely back into the denser medium.

Front

What is the critical angle?

Back

The critical angle is the angle of incidence above which total internal reflection occurs. It can be calculated using the formula: sin(θc) = n2/n1.

Front

What is the relationship between the speed of light and the index of refraction?

Back

The higher the index of refraction, the slower light travels in that medium. This relationship is expressed as n = c/v.