Education

  Life processes     •   Constantly exhibit the functions of maintenance and repair in living organisms     •   Some Examples- Digestion, Respiration, Circulation etc. Nutrition     •   Process of obtaining nutrients from the environment i.e. intake of food and then its digestion in the body.     •   Two types – Autotrophic (self-sufficient for food) and Heterotrophic (dependent on others for food). Autotrophic nutrition     •   Synthesis of food by photosynthesis- ‘photo’ means light and ‘synthesis’ means production. It is the production of food with the help of sunlight.     •   Photosynthesis equation-           6CO 2 +6H 2 O give C 6 H 12 O 6 +6O 2     •   Events of photosynthesis are as ...

  Refraction of Light Refraction of Light :  Happens in Transparent medium when a light travels from one medium to another, refraction takes place. A ray of light bends as it moves from one medium to another Refraction is due to change in the speed of light as it enters from one transparent medium to another. Speed of light decreases  as the beam of light travel from rarer medium to the denser medium. Some Commonly observed phenomenon due to Refraction Your eyes. Rainbows. Light bending in a glass of water. Glasses. Camera lenses. Object dislocation in water. Binoculars.. Refraction through a Rectangular Glass Slab When a incident ray of light AO passes from a rarer medium (air) to adenser medium (glass) at point. O on interface KL, it will bends towards the normal. At ptO1, on interface NM the light ray entered from denser medium(glass) to rarer medium (air) here the light ray will bend away from normal OO1 is a refracted ray OB is an emergent ray. If the incident r...

  LIGHT REFLECTION  Light is a form of energy, which gives us the power of vision. In this chapter we will study the phenomena of reflection and refraction using the property of light i.e. straight line propagation (Light wave travel from one point to another, along a straight line). Ray of light : It is a line in the direction of movement of light. Beam of light : It is bucnh of rays of light. Parallel beam : All the rays are parallel. Reflection of Light When the light is allowed to fall on highly polished surface, such as mirror, most of the light gets reflected. Laws of Reflection 1. The angle of incidence is always equal to angle of reflection. 2. The incident ray, reflected ray and the normal to the reflecting surface at the point of incidence lie in the same plane. Image formed by Plane Mirror  (Plane reflecting surface) 1. Virtual (imaginary) & Erect : The image that do not form on screen. Real images can be recorded on the screen. 2. Laterally inverted (...