![]() Beam of Light: A collection of number of rays of light is called beam of light.ġ1. Ray of Light: The path along which light energy travels in a given direction is called ray of light.ġ0. Extended Source of Light: Any source of light which is bigger than point source of light is called extended source of lightĮxamples: Bulb, Tube light, burning candle etc.ĩ. Point Source of Light: A source of light which is of the size of pinhead is called point source of light.Įxample: The pinhole act as a point source of light.Ĩ. Opaque Bodies: The bodies which do not allow the light energy to pass through them are called opaque bodies.ħ. Translucent Medium: A medium which partially allows the light energy to pass through it is called translucent medium.Įxamples: oiled paper, tissue paper, ground glass, butter paper etc.Ħ. Transparent Medium: A medium which allows most of the light energy to pass through it is called transparent medium.Įxamples: Vaccum, glass, clear air, alcohol, benzene etc.ĥ. Heterogeneous Medium: An optical medium, which has different composition at different points is called heterogeneous medium.Įxamples: Air, muddy water, fog, mist, clouds, smoke etc.Ĥ. Homogeneous Medium: An optical medium which has a uniform composition throughout is called homogeneous medium.Įxamples: Vaccum, diamond, distilled water, pure alcohol etc.ģ. Optical Medium: Any material (or) non-material through which light energy passes wholly (or) partially is called optical mediumĢ. Non-luminous Bodies: The bodies which do not give light energy by themselves, but reflect the light energy falling on them are called non-luminous bodies. Examples: The sun, the stars, glow worm etc. Luminous Bodies: The bodies which give out light energy by themselves are called luminous bodies. It means the speed of light is 300000000 m/s or 300000 km/s. Speed of Light: Light travels at very fast speed i.e., 3 × 10 8 m/s. In addition to it, lighted bulb, a fluorescent tube, a lighted candle ,a kerosene oil lamp, etc., are other sources of light. Sources of Light: Sun is the primary source of light for mankind. ![]() Thus, we can conclude that light is an invisible energy which causes in us sensation of vision. It is the brain which finally makes out the colours of the poster. The various colours reflected from the poster excite the retina of the eye, which in turn sends a message to the brain. It must be kept in mind that light energy makes the surrounding objects visible, but by itself it is an invisible energy.Įxample: If we are seeing a coloured poster, then we are seeing only the poster and not the coloured lights reflected fronts it. Since light is obtained from heat energy, i.e., when an object is heated to a temperature beyond. It shows that for vision the presence of light is essential.ĭefinition of Light: It is an invisible energy which causes in us sensation of sight (vision). However, if a bulb is switched on, everything in the room becomes visible. ![]() If we enter a dark room, objects present there are not visible. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |