S N Physics Expert

Mirror formula | Class 10 science | Concave mirror | Convex mirror | Physics Spherical Mirror :A mirror which is a part of a sphere is called spherical mirror. Kinds of spherical mirror :Spherical mirrors are of two types. These are (a) Concave mirror or Converging mirror (b) Convex mirror or Diverging mirror Convex mirror : Convex mirrors or diverging mirrors are those mirrors in which the reflecting surface is curved outwards. Concave mirrors : Concave mirrors or converging mirrors are those mirrors in which the reflecting surface is curved inwards. Some terms related to spherical mirrors: Centre of curvature (a)The centre of curvature (C) of a spherical mirror is the centre of the hollow sphere of glass whose part is spherical mirror. (b) It is generally denoted by 'C' . Radius of Curvature ● The radius of curvature (R) of a spherical mirror is the radius of the hollow sphere of glass, of which the spherical mirror is apart. Pole of spherical mirror ● The pole (P) of a sphe...

Light | Reflection of Light | Laws of reflection | Classs 10 physics Here we study class 10 physics,optics,light,reflection of light,laws of reflection,plane mirror,reflection by plane mirror,theory of light. Light 1. Light is a form of energy which enables us to see an object. 2.It is an electromagnetic wave. 3.Light waves are transverse in nature. 4.Light waves are electromagnetic radiation so they do not need a material medium to  travel. 5.It travels in vacuum as well as in material transparent medium. 6. The speed of light is 300000km/s in vacuum. 7.The speed of light in material medium is less than in vacuum. 8. Light travels in a  straight line. 9.Light is the fastest messenger in the universe. Theory of Light There are four theories of light. These are 1 . Newton's Corpus cular Theory of Light  : It explains corpuscles/particles nature of light.It proves rectillinear propagation of light, Reflection of light,Refraction of light. It does not prove interference of ...

  Hertz, Hallwacks and Lenard's observation on Photoelectric effect Hertz observation The phenomenon of photoelectric emission was discovered by Heinrich Hertz in 1887, when he was working with his electromagnetic wave experiment. When suitable radiations fall on a metal surface,some electrons near the surface observe enough energy from the incident radiation. Due to it, they are able to overcome the attraction of the positive ions in the material of the surface and escape to the surrounding space. Hallwacks and Lenard’s observation Hallwack and Lenard made a detailed study of the Photoelectric effect during 1886 to 1902. They observed,” when ultraviolet radiation falls on an emitter plate that is positive plate electrons are emitted from it which are attracted towards the other metal plate called collector plate kept at positive potential.The flow of electrons through the evacuated glass tube results in the current flow in the external circuit.  Thus light falling on the surf...