Physics

Introduction to waves * Waves are series of disturbances which propagate from a source to the surroundings or a destination. * Waves are classified into three types:    • Mechanical waves    • Electromagnetic waves    • Matter waves * Mechanical waves are governed by Newton’s laws and need a medium to propagate. * Electromagnetic ... Read more

Periodic and oscillatory motions * Motion which repeats itself after a fixed interval of time is called periodic motion. * The to-and-fro motion of a body is called oscillatory motion. * All oscillatory motions are periodic motions. But every periodic motion need not be an oscillatory motion. * Simple harmonic motion is the to-and-fro motion ... Read more

Molecular nature of matter * Kinetic theory was developed successfully by Maxwell, Boltzmann Brown and others. * Kinetic theory explains the behavior of gases based on the idea that a gas consists of atoms or molecules which are in random motion. * Dalton’s atomic theory proposes that every element is made up of tiny particles ... Read more

Thermal equilibrium and Zeroth law * Thermodynamics is the study of “exchange of ‘heat’ and ‘work’ between a system and its surrounding “, and the “resultant changes in the macroscopic variables of the said system”. * A thermodynamic system is an isolated body or a group of bodies with a well defined boundary. * The ... Read more

Temperature and heat * Heat is defined as a form of energy that flows from hotter body to a colder body when they are in thermal contact. * When two bodies are in thermal contact and there is no net exchange of heat, then they are said to be in thermal equilibrium. * The physical ... Read more

Physical quantities –fluids * A fluid is any matter that has tendency to flow. All liquids and gases are together referred to as fluids. * External force acting per unit area on a solid is called stress. * Pressure is defined as force exerted per unit area. * Density of a fluid is the ration ... Read more

Elastic behaviour of solids * When a force acts on a body, it accelerates in the direction of the net force. * When a set of equal and opposite forces acts on a body, there is no net force on the body but it gets deformed, changing its size or shape or both. * The ... Read more

Kepler’s Law of Gravitation * To resolve shortcomings of the models propounded by Ptolemy and Copernicus, * Kepler propounded three laws on planetary motion. * Kepler’s first law, the law of orbits, states that the orbit of a planet is an ellipse with the sun at one of the foci. * An ellipse is a ... Read more