Chapter 18 mirrors and lenses seneca valley school district. Investigating mirrors explore with plane mirrors mirror images, mirror writing, paired mirrors. The principal focus of a convex mirror is a point on its principal axis from which a beam of light rays, initially parallel to the axis, appears to diverge after being reflected from the convex mirror. Convex mirror is a curved mirror for which the reflective surface bulges out towards the. While clicking on the concave mirror button, a concave mirror, object and its image will be displayed in the window. If you can use the same format i did ill give 5 stars.
If the mirror is curved light hitting different points on. Convex mirrors center of curvature and focal point both located behind mirror. Light and optics truefalse decide whether each of the following statements is true or false. The concave mirrors, curved as the inside of a bowl, are used for focusing light, and the images often appear larger and upside down to the original object. By and large, convex and concave mirrors are the two types of spherical mirrors with many uses which is not possible with a plane mirror.
Convex mirror for a convex mirror, the radius of curvature is inside the mirror. Measure and graph image distance versus object distance for a convex mirror. What is the radius of curvature of a concave mirror that magni fies by a factor. A convex mirror is a spherical reflecting surface or any reflecting surface fashioned into a portion of a sphere in which its bulging side faces the source of light. Move the arrow to the right side of the mirror to get a convex mirror. A concave mirror which is also called as converging mirror has its reflecting surface bulging inwards, i. The surface may be either convex bulging outward or concave. Move the point named focus to change the focal length.
A convex mirror can only produce a virtual image since all reflected rays will diverge. The purpose of this activity is to measure the focal length of a concave mirror. This lesson pack enables you to teach your children about convex and concave mirrors, and devices and inventions that use these mirrors. Identify the focus and focal length of a curved mirror. Basic lenses and mirrors come in two different kinds.
Concave mirror cardboard screen masking tape convex mirror holders clay for mirror, metric ruler 2 meter sticks screen and light source light source procedure. The law of reflection applies, just as it does for a plane mirror, i. Two concave mirrors are placed on same principal axis. When you look at the backside of the spoon your upright reflection will be seen. The type of the image depends on the distance between the object and the mirror. Aug 25, 20 4 identify some of the concepts of the spherical mirrors and lenses. Convex mirrors give an erect, virtual, full size diminished image of distant objects. Where will the image form if the same object is placed 15 cm in front of a convex mirror with a focal length. Children will investigate how images change in the different mirrors, and will identify the types of mirrors used in modern day inventions. The difference between concave and convex mirror can best be understood by holding a polished spoon. Physics mcqs for class 12 chapter wise with answers pdf download was prepared based on latest exam pattern.
Define the following terms in relation to concave spherical mirror. Concave mirrors are curved mirrors that bulge inward. Ray hits the vertex of mirror 1 and reflects with same angle. Broadband metallic mirrors provide a good combination of performance and value over a very broad spectral range and are relatively. Activity 5 curved mirrors goals in this activity you will. An image which can be formed on the screen is known as real image and the one which cannot be formed on screen is known as a virtual image. The most common nonspherical type are parabolic reflectors, found in. Lets explore the ray tracing technique to figure out the properties of images when things are kept in front of a concave or a convex mirror.
Concave mirror problems and solutions solved problems. Why do we prefer a convex mirror as a rearview mirror in vehicles. Concave and convex mirrors unlike light rays hitting a flat mirror, parallel light rays reflecting off a curved mirror do not move in the same direction. Mirrors near the entrance are convex to make the shopper feel fat, but mirrors in the dressing rooms are concave, to m. Applications and uses of concave mirror in daily life byjus. Looking at the outside of the bowl, you would see the surface curving away in all directions.
Simulation of image formation in concave and convex lenses. They should try to describe any images they form in terms of magnification, upright or inverted, real or virtual. Difference between concave and convex concave vs convex. Description simulation of image formation in concave and convex mirrors. One mark questions convex mirror for seeing traffic at. Feb 06, 2017 convex mirrors reflect light outwards. On the other hand, a convex lens is thicker in the middle and thinner at the edges. A concave mirror a concave mirror has a shape with a thinner middle and thicker sides in relation to a flat plane. Concave mirrors are also called as convergence mirrors, because concave mirrors cause the incoming parallel rays together and it causes these rays to converge. Reflection and the ray model of light lesson 3 concave mirrors.
Mirror formula with solved numericals class 10 teachoo. Lenses concave and convex apparatus selection of lenses, collimated light source, e. The mirror used is a concave mirror or a convex mirror. Image formation lenses convex converging lens laws of refraction and reflection can be used to explain how lenses and mirrors operate parallel rays e. The minus sign indicates that the focal point of convex mirror is virtual. In a reflector telescope, light from the object of interest enters the far end of the telescope and strikes a concave mirror at the end closest to the viewer. There will be a window having two buttons named concave mirror and convex mirror. Images formed by concave and convex mirrors and determination. A spherical mirror is a part of a spherical reflecting surface. The concave mirror can give erect and enlarged image when the object is placed between pole and focus. The surface may be either convex bulging outward or concave recessed inward. Most curved mirrors have surfaces that are shaped like part of a sphere, but other shapes are sometimes used in optical devices.
Convex mirrors are used in many department stores and offices, most often placed in the corners of rooms, so that more of a particular room area may be seen at the same time. The halfway point between the centre of curvature and the pole. Let us find out what are mirror and lenses, phenomenas associated with them, applications, convex lens, concave lens, convex mirror, concave mirror in the form of mcqs. A curved mirror is a mirror with a curved reflecting surface. We offer an extensive variety of optical mirrors to provide an ideal solution for almost any application. Compare plane mirrors, concave mirrors, and convex mirrors. Objects at distances closer than r2 have virtual images behind the mirror while objects further away than r2 have real images in from of the. Concave and convex are also two types of spherical mirrors. The image is close to the mirror, upright, small and virtual. It is also possible to combine thin lenses and mirrors.
Also from our rule for s, we observe this is negative in the above drawing. They also have different properties of reflection and production of image. Aug 24, 2017 the detailed explaination about concave and convex mirrors is as follows. This is often used as a psychological trick in clothing stores. Broadband dielectric mirrors offer near total reflection over a wide spectral range and are very durable. A concave lens is thinner in the middle and thicker at the edges. For plane mirrors, the object distance equals the image distance and all images are erect and virtual.
Eight important differences between convex and concave lens are compiled in the article in tabular form. It might help you to remember this if you think that when you look in a concave mirror, it looks like you are. A mirror is a part of a smooth and highly polished reflecting surface. How to predict where the image of an object is, in a convex mirror. Notes, exercises, videos, tests and things to remember on images formed by concave and convex mirrors and determination of focal length. To investigate the properties of curved mirrors, and the characteristics of the images produced by curved mirrors. We would like to suggest that you combine the reading of this page with the use of our optics bench interactive or our name that image. The focal length of a convex mirror is 10 cm and the object distance is 20 cm. Curvedspherical mirror a curved mirror is a mirror with a curved reflecting surface. Describe what is meant by gaussian or paraxial optics.
Lenses convex concave optical instruments mirrors convex concave. To create a real image with a concave mirror, the object must be outside the focal point. The two mirrors are diametrically opposite to one another and produce different images at different positions. They should try to describe any images they form in terms of magnification, upright or inverted, real or. A concave lens diverges lightscatters it and cannot bring it into focusand the image that it forms shows up on the same side as the light it is. Difference between convex and concave mirror convex vs.
The convex is curved like the outer surface the ball. A 10 mm long awl pin is placed vertically in front of a concave mirror. This is why they show up in sideview mirrors on cars and in security mirrors on roads and in stores. Focal length of a concave mirror university of texas at. Types of mirrors figure 1 shows the three types of mirrors we will consider. Concave mirrors are also used in solarpowered gadgets and visual bomb detectors. Consider a concave mirror radius 10 cm then cm r f. Conversely, the concave lenses are thinner at the centre and thicker at its edges, in. Convex mirrors are often used in the hallways of buildings including stores, schools, hospitals, hotels and apartment buildings. A convex spherical mirror has the silvered surface of the mirror on the outer. On the contrary, in a concave mirror, the reflecting surface bulges inwards the main difference between a convex and concave mirror lies in the image formed by the two mirrors, i. Concave and convex mirrors ray diagram for convex and. For converging mirrors and diverging mirrors, the focal length is equal to onehalf the radius.
We have another rule, that when the curvature center c is on the same side of the outgoing ray, then the radius is positive. You will also verify the mirror and lens equation and the magnification formula by direct measurement of the positions of object and image. Also, they have a wider field of view as they are curved outwards. Move the tip of the object arrow to move the object. A ray passing through the focus of a concave mirror or proceeding toward the focus of a convex mirror is reflected parallel to mirror axis. A convex lens is known as a converging lens, whereas a concave lens is also known as a diverging lens. A mirror is a surface which reflects a clear image. One such difference is the structure of convex lens is like, thicker at the centre and thinner at the edges. There are two types of spherical mirrors convex mirror and concave mirror. If the outside surface is polished, is it a convex mirror. Apr 26, 2009 concave mirrors have a arched surface of reflection that is bulged in caved. Free pdf download of cbse physics multiple choice questions for class 12 with answers chapter 9 ray optics and optical instruments. In a convex mirror, parallel light rays move away from each other, as you can see in the diagram below on the left. Instead of a flat piece of glass, imagine a large, round bowl.
All images formed from convex mirrors are erect, virtual, and diminished in size. A lens is made of transparent material with a refractive index larger than air. This handson activity allows your students to discover the difference between reflections in concave and convex mirrors for themselves using spoons. These types differ in how and where they focus light. Snc 2d light and geometric optics convex mirrors extra practice worksheet a draw a ray diagram for each to locate the image. Convex mirrors have reflective surfaces that curve outward. A mirror is curved outward, like the bottom of a spoon. Apr 06, 2012 this video demonstrates and discusses ray diagrams for concave and convex mirrors. Determine a the image distance b the magnification of image. Each mirror has a radius of curvature r which is in. It is used in the aircraft landing to guide the airplanes, it is used as a torch to reflect the light rays, it is used during shaving to get an erect. Chapter 34a reflection and mirrors geometrical a powerpoint presentation by paul e.
Theory analysis of the geometry in ray diagrams for spherical curved mirrors and thin concave and convex lenses give us a relationship between the position of the object s, the position of the. The plane mirror is a flat surface, where the object reflected has an image the same size. Geometrical optics in the study of how light behaves, it is. They determine if images are real or virtual, if they are upright or inverted, the focal length of the. With mirrors, the curved surface is referred to as either concave or convex depending upon whether the center of curvature occurs on the side of the reflecting surface or the opposite side. Concave and convex are two classes of spherical mirrors.
This demo uses spoons to show students the difference between a reflections created by curved mirrors and how distance from the mirror changes the ref. They are used in driveways, roads, and alleys to provide safety to all the bikers and motorists at curves and turns and other places where there is a lack of visibility. Each face of the lens is part of a sphere and can be convex, concave. Optics exam2 and problem solutions physics tutorials. A light bulb is 60 cm from a concave mirror with a focal length of 40 cm. You must understand the differences between these two kinds of mirrors, be able to draw ray diagrams for both kinds of mirrors, and be able to solve the lens equation for both kinds of mirrors. Background concave and convex mirrors are examples of spherical mirrors. Move the tip of the object arrow or the point labeled focus. Students can solve ncert class 12 physics ray optics and optical instruments mcqs pdf with answers to know their preparation level.
Shop security mirrors shopkeepers install convex mirrors at different places on their shop this help them keep track of thieves and shoplifters since these mirrors give wide field of view, a large portion of shop can be seen with the help of a single mirror use of concave mirrors we saw that, image formed by concave mirrors is. Convex mirror uses of convex mirror definition equation. Applications and uses of concave and convex mirrors teachoo. All of them are segments of spheres centered on a horizontal axis. Now, we can combine these ideas by using mirrors that are curved to produce images. A concave mirror is a mirror that is curved inward in the middle.
Figure 33b shows the reflection of several light rays at a curved mirror. Physics mcqs for class 12 with answers chapter 9 ray. In order for the tooth hole to be clearly visible by the doctor, the mirror used should be able to enlarge the image of the tooth and the image must be upright. Activity 5 curved mirrors woodstownpilesgrove regional. Uses of convex mirrors mirror at concealed entrances, mirror to deter shoplifters, and car door mirrors. A 5 mm long image of the awl pin is formed at 30 cm in front of the mirror. In this lesson, learn about the types of images that can be formed by a convex mirror and some of the uses of convex mirrors. Ray, coming from first mirror turns back with same path after reflecting from second mirror. They are also referred to as converging mirrors, because as the light falls on the mirror, it collects the light and refocuses the parallel incoming rays. Convex mirror always produces inverted images and the size of the image is smaller than the size of the object. A wide variety of convex and concave mirrors options are available to you, such as metal, glass. Curved mirrors are roughly divided into two categories, concave and convex, terms that are also used to describe the geometry of simple thin lenses.
If the inside surface of the spherical mirror is polished, it is a concave mirror. A concave mirror is a spherical mirror in which the reflecting surface and the center of curvature fall on the same side of the mirror. Convex mirror problems and solutions solved problems. The plane and the convex mirrors can make only virtual images, but a concave mirror can make both virtual or real images. In this spherical mirrors worksheet, students answer 14 questions about convex and concave mirrors and the images formed in each. A ray diagram shows the path of light from an object to mirror to an eye. Move the point named focus to the right side of the lens to change to a concave lens. The cartesian sign convention is used here using a ray parallel to the principal axis and one incident upon the center of the mirror, the position of the image can be constructed by backprojecting the rays which reflect from the mirror. The terms concave and convex are from the perspective of the object. Observe real and virtual images in a concave mirror. Concave and convex the concave mirror is curved like the inner surface of the ball. Convex mirrors are useful because by demagnifying they squeeze a lot of the world into a small image, so they allow us to look in lots of directions at once. The surface may be either convex bulging outward or concave bulging inward.
Remember that 0 for concave and terminology scoilnet. The two other most common types of mirrors are the ones you ask about. Since a concave mirror converges a parallel beams of light rays, it is also called converging mirror. A spherical mirror is a mirror which has the shape of a piece cut out of a spherical surface. Three types of mirrors are plane mirrors, concave mirrors and convex mirrors.
Investigating refraction explore a selection of magnifying glasses, telescopes, binoculars, cameras. There are numerous uses of concave mirror in daily life. Use a light source, concave mirror, and half screen accessory on an optics bench to measure the focal length of the concave mirror. Quiz on mirrors ian upright object is located in front of a convex mirror a distance greater than the focal length. Difference between convex and concave lens with figure. The lateral magnification of the mirror or lens is the ratio.