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Reflection of light from Spherical Mirrors

A spherical mirror is that mirror whose reflecting surface is the part of a hollow sphere of glass. Spherical mirrors are of two types: concave mirrors and convex mirrors. In a concave mirror reflection of light takes place in the bent in surface or concave surface. In a convex mirror the reflection of light takes place at the bulging-out surface or convex surface.

Reflection of Light

Light is a form of energy which enables us to see objects and the straight line along which it travels is called ray of light. Reflection of Light is the process of sending back the light rays which falls on the surface of an object. The image formed due to reflection of an object on a plane mirror is at different places.

Magnetic effects of Electric Current

A current carrying conductor creates a magnetic field around it, which can be comprehended by using magnetic lines of force or magnetic field lines. Magnetic field in a current carrying straight conductor is in the form of concentric circles around it. The direction of magnetic field; in relation to direction of electric current through a straight conductor can be depicted by using the Right Hand Thumb Rule which is also known as Maxwell’s Corkscrew Rule.

Waves

A wave is a phenomenon whereby energy is moved without the transference of any material. X-rays, ultraviolet rays, light and radio waves all travel at the same speed through a vacuum.

The Kinetic Theory Of Matter

When a red hot piece of iron cools down, it transfers energy to its surroundings in three possible ways: conduction, convection or radiation.

The Four Fundamental Forces

The interactions between matter can be explained by four forces.

Special And General Theories Of Relativity

Special theory of relativity was formulated by Einstein.

Radioactivity

Radioactivity was gradually understood in terms of the disintegration of atomic nuclei. The three types of radiation are alpha decay, beta decay and gamma decay. Alpha radiation occurs when an unstable nucleus breaks down so as to eject a fast-moving nucleus of helium, which consists of two protons and two neutrons.

Nuclear Fission And Fusion

Otto Hahn and Fritz Strassman (1902-80) discovered nuclear fission in 1938. When an isotope of uranium-235 was bombarded with neutrons, it split into two lighter nuclei along with, on average, three neutrons. These neutrons were capable of bombarding and splitting other nuclei, causing more fission to take place.

Motion And Mechanics

Kinematics covers a broad range of topics, from bodies falling to earth, to the description of bodies moving in a straight line, to circular motion.

Introduction to Physics

Physics is the study of the basic laws that govern matter.

Heat and Work

Modern physics sees heat as energy collectively possessed by the particles making up a gas, liquid or solid. A body which possesses energy has the ability to do work.

Electromagnetism

Electromagnetism is the study of the effects caused by stationary and moving electric charges.

Electric Current

In the late 1790s, Count Alessandro Volta made the first battery. The first practical primary cell (non-rechargeable) was produced by John Frederic Daniell (1790-1845) in 1836, using zinc and copper electrodes. This was followed by the first secondary (rechargeable) cell invented by Gaston Plante (1834-89) in 1859.

Atomic Theories

John Dalton revolutionized science in 1803 when he hypothesized that atoms of different chemical elements, such as hydrogen and oxygen, had different characteristic masses. J.J. Thomson discovered the first subatomic particle -the electron - in 1897.

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