physics quantum mechanics

What is Physics? - The word 'Physics' comes from the Greek word 'phusis' meaning 'nature', introduced by the ancient scientist 'Aristotle'. Man has always been fascinated by nature. So, he questioned and sought answers for every phenomena nature could offer. The branch of scienc..

Under certain experimental conditions, a beam of particles (for example, electrons ) can exhibit wavelike properties. Such matter waves are governed by the laws of quantum physics. The wavelength is inversely proportional to the momentum of the particles. These are also known a..

Introduction - In the nineteenth century scientists saw enough evidence to prove that each element has its distinctive atom. But all tem atoms contain identical electrons. In spite of the fact that electrons carry negative charge, atoms as whole were found to be neutral. This led to the fact that a..

A mechanical wave is a periodic disturbance, which requires a material medium (solid, liquid or gas) for its propagation. These waves are also known as elastic waves because their propagation depends upon the elastic properties of the medium through which they pass. Examples for mech..

Electromagnetic waves returned to Earth by one of the layers of the ionosphere appear to have been reflected. In actual fact, the mechanism involved is refraction. As the ionisation density increases for a wave approaching the given layer at an angle, so the refractive index of the layer..

>Later, Joule's work lead to a new branch of physics known as thermodynamics conversion of heat energy into mechanical energy. In fact any form of energy, mechanical, electrical, chemical energy can be very easily converted to heat energy. Similarly, heat energy may al..

Mechanical Waves and Electromagnetic Waves - Depending upon their propagation in a medium, the waves are classified as follows: Mechanical waves or elastic waves and Electromagnetic wave..

We know that there is a transfer of energy, as heat, between a system and its environment. Here we discuss how this transfer takes place. There are three mechanisms of heat transfer. They are conduction, convection and radiatio..

Illustration of Conservation of Mechanical Energy - Conversion of gravitational potential energy to kinetic energy: When a body falls from a certain height, its kinetic energy increase..

Conservation of Mechanical Energy - We can see many situations in which energy is transferred to or from objects and systems, similar to money being transferred between accounts. In each situation, we assume that the energy that was involved can be accounted for, that is, energy cannot ap..