Extra Question Chapter 1:Chemical Reaction And Equations
Extra Question II Chapter 1:Chemical Reaction And Equations
Extra Question Chapter 2:Acid Ans Base
Important Question Chapter 3:Metal and Non Metal
Chapter 4:Carbon And Its Compoundl
Chapter 5:Periodic Classification of elememt
Chapter 7:Control and coordination
Chapter 8:How Do Organisms Reproduce?
Chapter 9:Hearedity And Evolution
Chapter 10:Light Reflection and Refraction
Chapter 11:The Human Eye and Colorful World
Light reflection is a phenomenon where light waves bounce back into the same medium upon hitting a surface. The laws of reflection state that the angle of incidence is equal to the angle of reflection, and the incident ray, reflected ray, and the normal to the point of incidence all lie on the same plane.s
Concave: mirrors are curved mirrors where the reflecting surface bulges inwards. They converge light rays to a single point known as the focus. They produce both virtual and enlarged as well as real and diminished images, based on the object's position. Convex mirrors have a reflecting surface that bulges outwards. They diverge light rays, making them appear as if they are coming from a particular point on the mirror. They produce images that are virtual, diminished, and upright
Refraction is the bending of light as it passes from one medium to another. This happens due to the change in speed of light in different media. The laws of refraction state that the incident ray, the refracted ray, and the normal to the interface of two media at the point of incidence all lie in the same plane, and the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant
The human eye functions much like a camera. The cornea in the eye is like a camera lens as it focuses light to create clear images. The iris and the pupil control the amount of light entering the eye, just like the aperture in a camera. The retina is akin to the film or image sensor in a camera, where the image is formed.
The principle of reversibility of light means that if the path of light is reversed, it will retrace its original path. This principle is used in ray diagrams to locate the image formed by lenses and mirrors.
A rainbow is formed due to the dispersion, refraction, and reflection of sunlight by water droplets in the atmosphere. Sunlight is first refracted as it enters the water droplet, then it gets reflected inside the droplet and refracts again as it leaves the droplet. The white light from the sun gets dispersed into its spectrum of colors, forming a rainbow.
The focal length of a lens is the distance between the center of the lens and the focal point. It is determined by the curvature of the lens surfaces and the material of the lens. A lens with a short focal length has greater optical power than one with a long focal length.
Concave lenses are used in a variety of optical devices like telescopes, eyeglasses, cameras, and binoculars. They are used in eyeglasses to correct short-sightedness. Convex lenses are used in devices like magnifying glasses, microscopes, and cameras. They are used in eyeglasses to correct long-sightedness.
Lenses form images by refracting light and focusing it at a point. Convex lenses converge light rays, forming a real image that can be projected on a screen. On the other hand, concave lenses diverge light rays, forming a virtual image that cannot be projected on a screen.
A prism is a transparent optical element with at least two polished, flat surfaces that are inclined to each other. The traditional geometrical shape is that of a triangular prism with a triangular base and rectangular sides. The most common type of prism is made of clear, transparent plastic or glass. A prism works by refracting, or bending, light. This happens because light travels at different speeds through different mediums. When light enters the prism, it is moving from air (one medium) into glass (another medium), which causes the light to slow down and change direction - this is refraction. The key to a prism's color-splitting ability lies in the different degrees of refraction for different colors of light. White light, like sunlight, is composed of multiple colors. When white light enters a prism, each color of light is refracted by a slightly different amount. Red light bends the least, while violet light bends the most. This causes the different colors to spread out and form a spectrum, also known as a rainbow. This property of prisms is used in various optical devices, such as binoculars and spectrometers, to manipulate light for various purposes.
A plane mirror forms a virtual and erect image of the object. The image formed is of the same size as the object and is located at the same distance behind the mirror as the object is in front of the mirror.
A real image is formed when light rays converge at a point. It can be obtained on a screen, is inverted, and can be larger or smaller than the object depending upon the position of the object relative to the lens or mirror..
The power of a lens is the measure of the degree of convergence or divergence of light rays achieved by the lens. It is the reciprocal of the focal length (in meters) of the lens. The power of a lens is measured in diopters.
A convex lens, also known as a converging lens, focuses the parallel rays of light that pass through it at a particular point. Hence, it is used in various optical devices such as a magnifying glass, camera, microscope, and spectacles for hypermetropic (far-sighted) individuals.r
A spherical mirror is a mirror which has the shape of a piece cut out of a spherical surface. There are two types of spherical mirrors: concave and convex. A concave mirror has the reflecting surface that bulges inwards. A convex mirror has the reflecting surface that bulges outwards.
Lateral inversion is the phenomenon due to which the left side of an object appears to be the right side in the mirror and vice versa. This is experienced when one looks at oneself in a plane mirror. .
The principle of reversibility of light states that light will retrace its path if the direction of the light is reversed. This principle is used in the ray diagrams of mirrors and lenses.
The focal length of a mirror is the distance between the pole (P) and the focus (F) of the mirror. For a concave mirror, the focal length is positive, and for a convex mirror, the focal length is negative.
A lens forms an image by bending light rays that pass through it. When light rays pass through a convex lens, they converge at a point on the other side of the lens. The point at which the rays meet is where the image is formed. For a concave lens, the light rays diverge, and the image is formed where the rays appear to originate from.
A concave lens is thinner at the center than at the edges, and it spreads out light rays that are incident on it. It forms a virtual, erect, and diminished image. A convex lens, on the other hand, is thicker at the center than at the edges. It bends the light rays towards a point, forming a real, inverted image (or a virtual, erect image, depending on the position of the object).