Table of Contents

## Does light take all possible paths?

The ‘simultaneous travel’ theory is a mathematical approach . It’s a way to explain why light takes the ‘easy road’ instead of looping around. In this example, the photon has a probability of traveling through all possible routes, each with a different probability.

### How does light choose the shortest path?

Fermat’s principle states that of all the possible paths the light might take, that satisfy those boundary conditions, light takes the path which requires the shortest time. Since the speed of light is the same everywhere along all possible paths, the shortest path requires the shortest time.

#### Who was the first to observe light travels in a straight line and always takes shortest path?

Galileo

**Who was the first to observe light travels in a straight line?**

The first person to realize that light actually travels from the object seen to the eye was the Arab philosopher “Alhazan” (whose real name was Abu’ali al-hasan ibn al-haytham), who published a book on optics in about 1000 AD. The law of reflection was correctly formulated in Euclid’s book.

**Why is light in hurry?**

Because it’s afraid of the dark.

## Is Fermat’s principle true?

In a reverse manner, if we consider that the Fermat’s principle is true, then we can derive the laws of reflection from (3) applying the derivative equal to zero. dy dx = 0 ‡’ y = f2(x) = stationary. Hence, Fermat’s principle is proved for refraction on a plane sur- face.

### Is Fermat’s principle correct?

Fermat’s principle, also known as the principle of least time, is the link between ray optics and wave optics. In its original “strong” form, Fermat’s principle states that the path taken by a ray between two given points is the path that can be traversed in the least time.

#### What does Fermat’s principle say?

Fermat’s principle, in optics, statement that light traveling between two points seeks a path such that the number of waves (the optical length between the points) is equal, in the first approximation, to that in neighbouring paths. It is useful in the study of optical devices.

**What are the two laws of reflection?**

Laws of reflection are: (i) The incident ray, the reflected ray and the normal ray at the point of incidence, lie in the same plane. (ii) The angle of incidence is equal to the angle of reflection. Want to top your physics exam ?

**What are the three laws of reflection?**

The laws of reflection are as follows: The incident ray, the reflected ray and the normal to the reflection surface at the point of the incidence lie in the same plane. The angle which the incident ray makes with the normal is equal to the angle which the reflected ray makes to the same normal.

## What does Snell’s law mean?

Snell’s law, in optics, a relationship between the path taken by a ray of light in crossing the boundary or surface of separation between two contacting substances and the refractive index of each. This law was discovered in 1621 by the Dutch astronomer and mathematician Willebrord Snell (also called Snellius).

### What is Snell’s law for?

Snell’s law (also known as Snell“Descartes law and the law of refraction) is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air.

#### How do you test Snell’s law?

The objective of this experiment is to verify the Snell’s law of refraction by tracking a laser ray passing through a rectangular slab of glass. Theory: Refraction is the abrupt change in the direction of light as it suddenly changes medium.

**In which condition Snell’s law is not applicable?**

Snell’s law is not applicable when angle of incidence is zero as the angle of refraction will also be zero.

**What is the formula of angle of refraction?**

Measure the angle of incidence – the angle between the normal and incident ray. It is approximately 60 degrees. Now draw the refracted ray at an angle of 34.7 degrees from the normal – see diagram below….A Lesson from the Laboratory.

Angle of Incidence (degrees) | Angle of Refraction (degrees) |
---|---|

85.0 | 48.5 |

## What does the angle of refraction depend on?

For any given angle of incidence, the angle of refraction is dependent upon the speeds of light in each of the two materials. The speed is in turn dependent upon the optical density and the index of refraction values of the two materials.

### What is the symbol for angle of refraction?

The angle of refraction, again named with the Greek letter theta, is called theta2.