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Particle Radiation

The atoms of all elements are made up of three particles called protons, neutrons and electrons. To understand the fundamental forces existing in the universe, it is important to learn about particles, subatomic particles, and their properties.

Particle Interactions

The fundamental particle interactions, also known as fundamental forces, are the interactions that do not appear to be reducible to more basic interactions.

Particle, Antiparticle & Photons

Every particle has an antiparticle, according to the standard model for describing fundamental particles and interactions. For example, the positron is the antiparticle of the electron.

Photoelectric Effect

Protons, neutrons and electrons that move around the nucleus constitute an atom. Some of the electrons in a metal are free to move around. These electrons are called free electrons.

Potential Divider

A potential divider is widely used in circuits. It is based on the principle that the potential drop across a segment of a wire of uniform cross-section carrying a constant current is directly proportional to its length.

Progressive Waves

Waves, which move from place to place without the transfer of matter, are called progressive waves. In this article, important properties of progressive waves are explained.

Projectile Motion

Consider a car that is moving in a straight line. The motion of the car is one-dimensional. Now, consider a ball kicked by a football player. 

Quarks & Anti-Quarks

In the classification of subatomic particles, as illustrated in Figure 1, Hadrons (Mesons and Baryons) are made up of three smaller particles called quarks. The types of quark are: up (u), down (d) and strange (s).


Refraction is the change of direction of wave that occurs when its speed changes. Refraction is a phenomenon that is exhibited by wave when it travels from one medium to another, for example, when light travels from air to glass or vice versa. 


All materials resist the flow of charges. The charges accelerate from one point of a circuit to another due to the potential difference between the two points.