Reflection

Isaac Newton's experiment in 1665 showed that a prism bends visible light and that each color refracts at a slightly different angle depending on the wavelength of the color.

A. Compared to objects with dull or unpolished surfaces, glossy or polished objects reflect more light. The best light reflector is made of silver metal.

As objects grow hotter, they radiate energy dominated by shorter wavelengths, changing color before our eyes. A flame on a blow torch shifts from reddish to bluish in color as it is adjusted to burn hotter. In the same way, the color of stars tells scientists about their temperature.

NASA’s Juno spacecraft entered orbit around Jupiter in 2016, the first explorer to peer below the planet's dense clouds to…

Notes forreflectionoflight

All electromagnetic radiation is light, but we can only see a small portion of this radiation—the portion we call visible light. Cone-shaped cells in our eyes act as receivers tuned to the wavelengths in this narrow band of the spectrum. Other portions of the spectrum have wavelengths too large or too small and energetic for the biological limitations of our perception.

Laser altimetry is an example of active remote sensing using visible light. NASA's Geoscience Laser Altimeter System (GLAS) instrument onboard the Ice, Cloud, and land Elevation Satellite (ICESat) enabled scientists to calculate the elevation of Earth's polar ice sheets using lasers and ancillary data. Changes in elevation over time help to estimate variations in the amount of water stored as ice on our planet. The image below shows elevation data over the West Antarctic Ice Streams.

Reflection, refraction diffraction

At home, we create our virtual image using plane mirrors. The image distance from a plane mirror will be equal to the object distance from the mirror. The light ray is reflected by a planar surface and is subject to the following two laws of reflection.

A. Yes, water can reflect light. Also, it refracts the light. When the light falls on the water surface some of the light gets reflected and some refracted into it.

Close examination of the visible-light spectrum from our Sun and other stars reveals a pattern of dark lines—called absorption lines. These patterns can provide important scientific clues that reveal hidden properties of objects throughout the universe. Certain elements in the Sun's atmosphere absorb certain colors of light. These patterns of lines within spectra act like fingerprints for atoms and molecules. Looking at the Sun's spectrum, for example, the fingerprints for elements are clear to those knowledgeable about those patterns.

Science Mission Directorate. "Visible Light" NASA Science. 2010. National Aeronautics and Space Administration. [insert date - e.g. 10 Aug. 2016] http://science.nasa.gov/ems/09_visiblelight

Specularreflection

There are two laws that govern the reflection of light (reflected from any surface). These Laws are referred to as laws of reflection. When light from any object reflects from polished surfaces, the reflection is called regular reflection. Regular reflection produces an image. We obtain two different types of images: real and virtual, depending on the mirror (reflecting surface) and object position.

A. The light coming from the sun falls on the moon and after the reflection from the moon it reaches the earth and thus we can see it. The portion on which the light falls appears bright and the rest appears dark.

Object : An object is everything which is viewed. Also it is the point of intersection of the incident rays. The object can be real and virtual. When the incident rays actually meet (or emerge from) the object is called a real object (figure 1). When the incident rays appear to meet (or emerge from) then it is called a virtual object (figure 2).

NASA explores the unknown in air and space, innovates for the benefit of humanity, and inspires the world through discovery.

Refraction oflight

Laser altimeters can also make unique measurements of the heights and characteristics of clouds, as well as the top and structure of the vegetation canopy of forests. They can also sense the distribution of aerosols from sources such as dust storms and forest fires.

Multiplereflection

Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…

The reflecting surface can be plane or spherical. In the above figure, a plane reflecting surface is shown. A parallel beam of light incident on the surface after the reflection is bounced back in the same medium.

National Aeronautics and Space Administration, Science Mission Directorate. (2010). Visible Light. Retrieved [insert date - e.g. August 10, 2016], from NASA Science website: http://science.nasa.gov/ems/09_visiblelight

Patterns are also evident in a graph of an object's reflectance. Elements, molecules, and even cell structures have unique signatures of reflectance. A graph of an object's reflectance across a spectrum is called a spectral signature. Spectral signatures of different Earth features within the visible light spectrum ARE shown below.

Image : The point of intersection of reflected rays is called image. It can also be real and virtual. If the reflected rays appear to meet then it is called a virtual image (figure 1). If the reflected rays actually meet at a point then it is called real image (figure 2).

Our Sun produces more yellow light than any other color because its surface temperature is 5,500°C. If the Sun's surface were cooler—say 3,000°C—it would look reddish, like the star Betelgeuse. If the Sun were hotter—say, 12,000°C—it would look blue, like the star Rigel.

The visible light spectrum is the segment of the electromagnetic spectrum that the human eye can view. More simply, this range of wavelengths is called visible light. Typically, the human eye can detect wavelengths from 380 to 700 nanometers.

When a light ray encounters a boundary between two different media and bounces back to enter the same medium, this phenomenon is referred to as the reflection of light. The ray which falls on the surface is called the incident light ray. The ray that bounces back is known as the reflected ray. If we draw a perpendicular on the reflecting surface, at the point of incidence it is called the normal. The point where a light ray coming from an item or source appear to meet after being reflected by a surface is called an image. We can see our surroundings because light reflects off a variety of surfaces.

A. The law of reflection is valid for all the reflecting surfaces including plane mirrors, concave mirrors and convex mirrors. Concave and convex mirrors have curved surfaces but at the microscopic level it can be considered to consist of an infinite number of a plane reflecting surfaces.

As the full spectrum of visible light travels through a prism, the wavelengths separate into the colors of the rainbow because each color is a different wavelength. Violet has the shortest wavelength, at around 380 nanometers, and red has the longest wavelength, at around 700 nanometers.

The Sun is the dominant source for visible-light waves our eyes receive. The outer-most layer of the Sun's atmosphere, the corona, can be seen in visible light. But it is so faint it cannot not be seen except during a total solar eclipse because the bright photosphere overwhelms it. The photograph below was taken during a total eclipse of the Sun where the photosphere and chromosphere are almost completely blocked by the moon. The tapered patterns—coronal streamers—around the Sun are formed by the outward flow of plasma that is shaped by magnetic field lines extending millions of miles into space.

Let's play an interesting game. First, keep your face in front of a dull wall and observe. Now see your face on your shining floor and note the observation. Now take a bucket of water and see your face in it and observe. At last, see your face in the plane mirror at your home. If you compare the observations of all four cases you will find there is no image of your face when you see it on the wall. There is an image with very poor quality when seen on the floor. When you see the face in the water still you can see the image but not clear. You got a proper image of good quality when seen in the plane mirror. Although all four are plane surfaces, still we are getting different quality images. This phenomenon can be understood by the reflection of light. The walls of the house are rough in nature so produce diffuse reflection and regular reflection is very less when light falls on it. On the other hand, the mirror reflects almost all the light that falls on it. Let's learn more about the reflection of light!