In a plane mirror the image is the same size as the object and the same way up. A concave amkeup mirror is designed so that a person 28. The surface may be either convex bulging outward or concave bulging inward. Theory when parallel light rays pass through a thin lens, they emerge either converging or diverging. The minus sign indicates that the focal point of convex mirror is virtual. How light is reflected from a concave mirror to produce real and virtual images. In that lesson, it was shown that concave mirrors can produce both real and virtual images, depending upon the object location.
This is a product that i created for my high school physics students. There are two types of spherical mirrors, convex mirror and concave mirror. Determine a the image distance b the magnification of image. A concave mirror has a radius of curvature of 24 cm.
During shaving, the concave mirror forms an enlarged and erect image of the face when the mirror is held closer to the face. There will be a window having two buttons named concave mirror and convex mirror. If the outside surface is polished, is it a convex mirror. Eight important differences between convex and concave lens are compiled in the article in tabular form.
If the outer side of the spherical mirror is reflecting, it is called a convex mirror. The primary goals are to understand the relationship between. Geometrical optics in the study of how light behaves, it is. Light ray rules for convex lens and concave lens are discussed. Optics exam2 and problem solutions physics tutorials. We now want to derive two simple equations which provide quantitative relationships among the quantities we have defined to describe mirrors, i. Dec 08, 2018 eight important differences between convex and concave lens are compiled in the article in tabular form. The terms concave and convex are from the perspective of the object. In other subjects, you learn in lessons and do homework at home. Difference between convex and concave mirror is one of the most important concepts in the topic of optics in physics. When parallel rays could be from a distant object incident on a concave mirror, the reflected rays converge to a focal point f, hence also called converging mirror.
You must be able to draw ray diagrams for plane mirrors, and be able to calculate image and object heights, distances, and magnifications. A mirror that bulges outwards is called a convex mirror. In lesson 4, we will follow a similar pattern of inquiry for convex mirrors. These labs require very little setup and could be used in centers or stations. The purpose of this lab is to introduce students to some of the properties of thin lenses and mirrors. Replace the convex mirror with the concave one and move it to the end of the track. Nov 15, 2017 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.
In this case, the focal point is behind the mirror. Ask your doubt of concave mirror and get answer from subject experts and students on topperlearning. Jun 16, 2018 the video in english explains about different types of mirror i. The detailed explaination about concave and convex mirrors is as follows. All images formed from convex mirrors are erect, virtual, and diminished in size. Frankl your own mind is a sacred enclosure into which nothing harmful can enter except by your promotion. Conversely, the concave lenses are thinner at the centre and thicker at its edges, in structure.
The concaveconvex mirror set is perfect for student explorations of mirror optics. Concave mirrors, geometrical optics from alevel physics tutor. Focal length of a concave mirror university of texas at. While plane mirrors always produce virtual images, concave mirrors are capable of producing both real and virtual images. The various lengths six lengths are relevant for mirrors. Snc 2d light and geometric optics convex mirrors extra practice worksheet a draw a ray diagram for each to locate the image. The formation of images by spherical mirrors imaging with convex mirrors ray 1 is initially parallel to the principal axis and appears to originate from the focal point. For physics, you have to learn at home through watching videos prepared by your physics teacher. All of them are segments of spheres centered on a horizontal axis. Read about properties of convex mirror and concave mirror at. Concave mirrors are also called as convergence mirrors, because concave mirrors cause the incoming parallel rays together and it causes these rays to. Stay tuned with byjus to know more about concave convex mirrors, plane mirrors and much more.
The directions are written directly to the students so you dont have to introduce them. 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. The physics convex lenses are converging lenses, and concave lenses are diverging lenses. The main difference between concave and convex mirrors is the most easily seen. A convex mirror can only produce a virtual image since all reflected rays will diverge. For concave mirror, the reflected rays converge to the focal. What is the sign convention to be taken while solving problems related to image or object distance in case of convex and concave mirrors. Pdf optical images due to lenses and mirrors researchgate.
If the object distance is greater than the focal length f then the concave mirror produces an inverted image. Concaveconvex mirror set of 6, 50mm arbor scientific. Theyre great additions to a study of light and optics. Science plane, concave and convex mirrors and reflection. Ray, coming from first mirror turns back with same path after reflecting from second mirror. Draw rays or 1s 1f 1s convex implies f problems and solutions. This lab could be done with the front and the back side of a spoon being used as a concave and a convex mirror. Three more labs to study plane, convex and concave mirrors. The radius of curvature r, which is positive for concave mirrors and. You must understand the differences between these two kinds of mirrors, be able to draw. For plane mirrors, the object distance equals the image distance and all images are erect and virtual.
Ray 2 heads towards the focal point, emerging parallel to the principal axis. There are two types of curved mirror convex and concave. Concave mirrors and convex mirrors image formation, ray diagram. The set includes a concave and a convex mirror with focal lengths of 10cm, 20cm, and 50cm. To create a real image with a concave mirror, the object must be outside the focal point. This packet includes practice problems for plane mirrors, convex mirrors, and concave mirrors. The mirror formula using the real is positive sign convention. This handson activity allows your students to discover the difference between reflections in concave and convex mirrors for themselves using spoons. In this article, we will learn about image formation by concave and convex mirrors. Chapter 34a reflection and mirrors geometrical a powerpoint presentation by paul e. Same procedure as for concave mirrors we did earlier. Concave mirrors are most commonly used in shaving because of its reflective and curved surface. The focal point is the same distance from the mirror as in a concave mirror. This is a four page packet of practice problems that is divided into sections so as not to discourage students.
We look at the image formation by these spherical lenses using ray diagrams. Ray hits the vertex of mirror 1 and reflects with same angle. Looking at the outside of the bowl, you would see the surface curving away in all directions. 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. Convex and concave lenses jonny nelson introduces an animated explanation of lenses a lens is a shaped piece of transparent glass or plastic that refracts light. The focal length of a convex mirror is 10 cm and the object distance is 20 cm.
Concave and convex mirrors ray diagram for convex and. If the inner side of the spherical mirror is reflecting, it is called a concave mirror. When these quantities are measured from the surface of the mirror or lens, the formula is. Lesson 3 focused on the reflection of light by concave mirrors and on the formation of images by this reflected light. Concave mirrors can form inverted and real images and also virtual and erect images. Worksheets on concave and convex mirrors teachers pay teachers. It explains about properties of different types of mir. The principal rays can be displayed, as well as rays drawn by the user. In order for the tooth hole to be clearly visible by the doctor, the mirror used should be able to. A virtual image is formed if the object is located less than one focal length from the concave.
When parallel rays could be from a distant object incident on a concave mirror, the reflected rays converge to a focal point f, hence also called converging. The two other most common types of mirrors are the ones you ask about. So far we have discussed concave and convex mirrors qualitatively and graphically. Convex mirror has two ray diagrams because its principal focus and the centre of curvature lies behind its reflecting surface. The mirror used is a concave mirror or a convex mirror.
One such difference is the structure of convex lens is like, thicker at the centre and thinner at the edges. Sign convention for spherical mirrors the sign conventions for the given quantities in the mirror equation and magnification equations are as follows. Convex and concave lenses purpose in this experiment, you will explore the difference between convex and concave lenses and determine their focal lengths. The video in english explains about different types of mirror i. Since a concave mirror converges a parallel beams of light rays, it is also called converging mirror. A convex mirror has a negative focal length because of this.
Spherical mirrors a modern compter hovers between the obsolescent and the non existent sydney brenner. There are two kinds of spherical mirrors, concave and convex. The focal point f of a concave mirror is the point at which a parallel beam of light is focussed after reflection in the mirror. 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. Spherical mirrors can be thought of as a portion of a sphere which was sliced away and then silvered on one of the sides to form a reflecting surface. In case of convex mirror, parallel rays are diverged. There is always a higher than usual level of risk associated with working in a science. For converging mirrors and diverging mirrors, the focal length is equal to onehalf the radius. The focal length f of the concave mirror is 4 cm, therefore the patients teeth should be less than 4 cm in front of a concave mirror.
Instead of a flat piece of glass, imagine a large, round bowl. Curvedspherical mirror a curved mirror is a mirror with a curved reflecting surface. Worksheets on concave and convex mirrors teachers pay. It might help you to remember this if you think that when you look in a concave mirror, it looks like you are. Difference between convex and concave mirror with comparison. Convex mirrors are used as rear view mirrors in vehicles such as cars. It will give a virtual upright image if the object is within the focal length. Place an object in front of a mirror of variable radius of curvature and observe the image that is formed.
Concave mirrors are used as shaving mirrors, as reflectors in flashlights and automobile headlights, and by doctors e. Figure 1 shows the three types of mirrors we will consider. Therefore, not more than two positions of the object can be obtained in relation to these points unlike concave mirrors where more than two ray diagrams are constructed to find out the position of the image for different relative positions of the object. The law of reflection applies, just as it does for a plane mirror, i.
Background concave and convex mirrors are examples of spherical mirrors. Applications and uses of concave mirror in daily life byjus. It is proven in introductory physics textbooks1 that the image and. Concave and convex mirrors are examples of spherical mirrors. Convex mirrors are used as rear view mirrors by drivers in vehicles and as reflectors in street lights.
Concave mirrors are also known as a converging mirror since the rays converge after falling on the concave mirror while the convex mirrors are known as diverging mirrors as the rays diverge after falling on the convex mirror. As shown above, real images are produced when the object is located a distance greater than one focal length from the mirror. Six different 50mm diameter spherical glass mirrors each feature a protected silver coating and is packed in a lined storage box. When parallel rays could be from a distant object incident on a concave mirror, the reflected. The difference between concave and convex mirrors is also one of the most commonly asked questions in the physics exams and in the competitive exams. Concave mirrors, geometrical optics from alevel physics.
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 image s, and the focal length f. Concave mirrors are silvered on the inside of the sphere and convex mirrors are silvered on the outside of the sphere. Two concave mirrors are placed on same principal axis. In convex mirrors, the principal axis is the same as in a plane or concave mirror, perpendicular to the center of the mirror. While clicking on the concave mirror button, a concave mirror, object and its image will be displayed in the window. Ray 3 travels toward the center of curvature and reflects back on itself. Concave mirrors are silvered on the inside of the sphere and convex mirrors are silvered on the. Mar 03, 2019 convex and concave lenses are spherical lenses. A concave mirror is a mirror that is curved inward in the middle. The purpose of this activity is to measure the focal length of a concave mirror. Difference between convex and concave lens with figure. A convex lens gives a real, inverted image if the object is outside the focal length of the lens.