# What is the speed of light in a Michelson interferometer?

• queenstudy
In summary, the speed of light is always constant at c in a vacuum. However, Michelson and Morley believed that light would travel at a speed of c+v if moving in the same direction as the aether and c-v if moving in the opposite direction. This was later found to be incorrect and the speed of light remains at c regardless of the direction it is traveling in relation to the aether.

#### queenstudy

can someone explain to me the speed of light to the mirror and back from the mirror before reaching the telescope ?? please

I'm sorry, I don't understand what you are asking. Could you elaborate your question a bit more?

sorry i shoudl have elaborated more , i mean why the speed of light from the half painted mirror to one of the two mirrors is c-v and c+v from the mirror to the painted mirror??

The speed of light in a vacuum is always c. Michelson and Morley erroneously thought that light would travel at c+v if it was moving in the same direction as the aether (which presumably travels at v), and c-v when moving in the opposite direction as the aether.

mmm i have read it you are right in everything but in the speed of c and ether c-v when angle between them is zero and c+v when they are opposite but thank you for all your help

## 1. What is a Michelson interferometer?

A Michelson interferometer is a scientific instrument used to measure small changes in distance. It consists of two arms, one with a fixed mirror and one with a movable mirror, and a light source that is split into two beams. The interference pattern created by the two beams can be used to measure changes in the length of one of the arms, making it useful for measuring small displacements, wavelengths, and refractive indices.

## 2. How does a Michelson interferometer work?

A Michelson interferometer works by splitting a beam of light into two beams using a partially reflective mirror. One beam travels along the fixed length arm, while the other beam travels along the movable arm. The two beams are then recombined and the interference pattern is observed. Any changes in the length of the movable arm will cause a shift in the interference pattern, which can be measured and used to calculate the change in distance.

## 3. What are the applications of a Michelson interferometer?

Michelson interferometers have a wide range of applications in science and technology. They are commonly used in precision measurement of length, wavelength, refractive index, and mechanical vibrations. They are also used in spectroscopy to measure the absorption and emission spectra of materials. Additionally, Michelson interferometers are used in gravitational wave detectors and in the fields of astronomy and optics.

## 4. What are the advantages of using a Michelson interferometer?

One of the main advantages of using a Michelson interferometer is its high precision and sensitivity. It can measure very small changes in distance, making it useful for a variety of scientific and technological applications. Additionally, it is a relatively simple and inexpensive instrument, and can be easily constructed and calibrated in a laboratory setting.

## 5. What are the limitations of a Michelson interferometer?

Although a Michelson interferometer has many advantages, it also has some limitations. One limitation is its sensitivity to external disturbances such as vibrations or temperature changes, which can affect the accuracy of the measurements. Additionally, it is only able to measure changes in distance along one direction, making it less useful for measuring multidimensional changes. Finally, it requires a stable and coherent light source, which can be difficult to achieve in some settings.