FreeNotes
Defects of Vision are conditions that cause the eye to not focus images properly on the retina, resulting in blurry or distorted vision. These defects can be corrected with the help of lenses or medical intervention. 1. Myopia (Nearsightedness) Definition: Myopia is a condition where a person can see nearby objects clearly, but distant objects … Read more
Astronomical Telescope: An astronomical telescope is an optical instrument designed to observe distant celestial objects like stars, planets, and galaxies. It uses lenses or mirrors to gather and magnify light, allowing astronomers to view objects that are too far away to be seen with the naked eye. Construction of an Astronomical Telescope: An astronomical telescope … Read more
A compound microscope is an optical instrument that uses more than one lens to magnify small objects. It is commonly used in laboratories for examining specimens like cells, bacteria, or thin slices of biological tissues. Construction of a Compound Microscope: The basic construction of a compound microscope involves several key parts: Eyepiece (ocular lens): This … Read more
Magnifying Lens or Simple Microscope: A magnifying lens or simple microscope is a single convex lens that is used to magnify objects. It works on the principle of forming a magnified image of a small object that is placed close to the lens. This type of microscope does not have multiple lenses like more complex … Read more
Resolving Power and Magnifying Power are two important terms used to describe the capabilities of optical instruments like microscopes and telescopes. 1. Resolving Power: Definition: Resolving power refers to the ability of an optical instrument to distinguish between two closely spaced objects. It is the minimum distance between two points at which they can still … Read more
A lens is a transparent optical device that bends light. Types: 1. Convex lens (Converging lens): Thicker in the center, brings light together. 2. Concave lens (Diverging lens): Thinner in the center, spreads light apart. Terminologies: Optical center (O): The center of the lens. Principal axis: A straight line passing through the center of the … Read more
Optical fibre is a thin, flexible strand of glass or plastic used to transmit light signals. Light travels through total internal reflection, bouncing off the inner walls without escaping. Used in communication, medical endoscopy, and networking. Related Questions: What is reflection of light? Define the following terms: Incident ray, reflected ray, normal, angle of incidence, … Read more
Total Internal Reflection (TIR) is a phenomenon in optics that occurs when a light wave traveling through a medium hits the boundary with another medium at an angle larger than a critical angle and is completely reflected back into the original medium. This means that no refraction occurs, and all the light is reflected. Necessary … Read more
The laws of refraction, also known as Snell’s Laws, describe how light behaves when it passes from one medium to another. These laws are fundamental in understanding how light bends when traveling through different materials. Laws of Refraction First Law of Refraction (Snell’s Law): The incident ray, the refracted ray, and the normal to the … Read more
Refraction of Light: Refraction is the bending of light as it passes from one medium to another due to a change in its speed. When light travels from a medium of one optical density to another, its speed changes, causing the light to bend. This bending of light is called refraction. The amount of bending … Read more