What Is Rectilinear Propagation Of LightUsually light travels in a straight line. When we want to represent the propagation of light with a diagram, we represent it with the help of rays and beams. Ray A ray is a line with an arrow that shows the direct…

Expansion and Contraction in Solids, Liquids and GasesSome materials expand on heating and some contract on cooling. Heating makes the particles (that form the material) expand or become loose. Cooling makes the particles (that form the material) contrac…

What is the use of magnet?Magnets have several uses:Credit cards, ATM cards, and identity cards have a strip of magnetic material that stores information.Television and computer monitors use magnets.Computer hard discs and audio and video cassettes have …

Image Reflection by a Plane MirrorCan you think of a plane reflecting surface? The mirror on the dressing table is a good example of a plane reflecting surface. Any smooth polished surface that can reflect the rays of light and form a clear image is call…

What are the Different Types of Magnets?Magnetism: The property due to which a substance attracts iron pieces towards it, is called magnetism. The substance having property of magnetism, is called magnet.There are two types of magnets: temporary and perm…

How does a magnet work?Attraction and Repulsion of Magnetic Poles When two magnets are brought close to each other, they are either pulled towards each other, or pushed away from each other. When the magnets are pulled towards each other, they are said …

What Is Measurement In PhysicsMeasurement is the process of finding the length, size, or quantity of a substance. Since ancient times, people have used several ways to measure length. A physical quantity (like length) has to be measured with respect to s…

Heating Effect Of Electric CurrentTry touching a torch bulb that is lit and another that is not. Be careful when you touch the lit bulb. Do you feel it is hot to touch? Why do you think it is so?In a bulb, an electric current passes through a very thin …

Types of Spherical Lenses Definition: A piece of a transparent medium bounded by at least one spherical surface, is called a spherical lens. An optical lens is made of transparent material such as glass or clear plastic. One or both surfaces usually hav…

Magnetic Effect Of Electric CurrentYou know that magnets can attract certain substances such as iron. So far, you have studied about electricity and magnetism separately. However, did you know that electricity and magnetism are closely related? Perform …