أكاديميا - كولنز - معاجم الجيب العلمية - الفيزياء - انكليزي - فرنسي - عربي الحرف ٤_ r

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reflection
reflexion f

reflection. One of three things that can happen to radiation in a medium when it encounters the surface of another medium (see absorption): The radiation bounces back into the first medium.

The laws of reflection enable us to find the place (direction) to which the incident ray will go after reflection at a certain point, which is the point of incidence (or point of incidence. We measure angles by their distance from the normal), that is, the line perpendicular to the surface at the point of incidence. See figure.
A) The reflected ray is on the same surface with the incident and incident ray.

b) The angle of reflection r equals the angle of incidence i.

See also mirror, image, diffuse reflection, total, lateral inversion, optical instruments, and internal reflection.

The reflection of water waves can be demonstrated through ripple tank experiments:

Reflection caused by a concave barrier
Reflection of (a) plane waves (b) and circular waves on a flat barrier.


refraction
reaction f

Refraction One of three things that can happen to radiation in a medium when it meets the surface of another medium. See absorption. Radiation often travels through the second medium in another direction.

The laws of refraction enable us to find the place or direction to which an incident ray will go after being refracted at a certain point, which is the point of incidence. We measure angles by their distance from the normal, that is, the perpendicular line to the surface at the point of incidence.

A) The refracted ray is on the same surface with the incident and incident ray.

b) For two specific media, the sine of the angle of incidence divided by the sine of the angle of refraction is constant. This constant is the refractive index, and it relates to the two speeds of radiation passing through the two media.
See also optical , mirage , lens , color rainbow , and instruments .


refractive index(n)
index m de refection

The presumption of refraction. When light passes through a vacuum (or
Air) into a denser medium. Light is refracted as it approaches the regulator within the denser medium.

n = sin i/sin r

This is caused by a change in the speed of light.

n = speed of light in a vacuum (or air)/speed of light in a medium

Refraction of water waves Ret

It also explains why the middle appears shallower than it actually is.

True depth/apparent depth = n