1. Using Mirrors to Form Images

2. Kinds of Mirrors Flat mirrors are called plane mirrors. Mirrors that curve inward are called concave mirrors. Mirrors that bulge outward are called convex mirrors.Flat mirrors are called plane mirrors. Mirrors that curve inward are called concave mirrors. Mirrors that bulge outward are called convex mirrors.

3. Kinds of Images in Mirrors : Virtual and Real Mirrors can form either virtual images or real images. A virtual image looks like it exists in a place but if the place is checked, no image can be located with a screen. Real images can be found and focused onto a screen. Light rays actually meet to form a real image but no light rays actually meet to form a virtual image.Mirrors can form either virtual images or real images. A virtual image looks like it exists in a place but if the place is checked, no image can be located with a screen. Real images can be found and focused onto a screen. Light rays actually meet to form a real image but no light rays actually meet to form a virtual image.

4. Concave Mirrors Converge Light Rays When parallel light rays strike a concave mirror, they reflect to a point called the focus. The distance from the mirror to the focus is called the focal length of the mirror.When parallel light rays strike a concave mirror, they reflect to a point called the focus. The distance from the mirror to the focus is called the focal length of the mirror.

5. Convex Mirrors Diverge Light Rays When parallel light rays strike a convex mirror, they diverge or spread out from each other.When parallel light rays strike a convex mirror, they diverge or spread out from each other.

6. Object and Image Distance in Plane Mirrors In plane mirrors, the image is always the same distance as the object from the reflecting surface of the mirror.In plane mirrors, the image is always the same distance as the object from the reflecting surface of the mirror.

7. Object and Image Distance in Plane Mirrors In plane mirrors, the image is always the same distance as the object from the reflecting surface of the mirror.In plane mirrors, the image is always the same distance as the object from the reflecting surface of the mirror.

8. Image Orientation in Plane Mirrors Images in a plane mirror are reversed left-to-right.Images in a plane mirror are reversed left-to-right.

9. Image Orientation in Plane Mirrors Images in a plane mirror are reversed left-to-right.Images in a plane mirror are reversed left-to-right.

10. How An Image is Formed in Plane Mirror Light rays from an object bounce off a mirror and diverge or spread apart towards the eye. The eye extends these rays to where they meet which is behind the mirror. Thus the eye sees an image where there really are no light rays, a virtual image.Light rays from an object bounce off a mirror and diverge or spread apart towards the eye. The eye extends these rays to where they meet which is behind the mirror. Thus the eye sees an image where there really are no light rays, a virtual image.

11. How An Image is Formed in Plane Mirror Light rays from an object bounce off a mirror and diverge or spread apart towards the eye. The eye extends these rays to where they meet which is behind the mirror. Thus the eye sees an image where there really are no light rays, a virtual image.Light rays from an object bounce off a mirror and diverge or spread apart towards the eye. The eye extends these rays to where they meet which is behind the mirror. Thus the eye sees an image where there really are no light rays, a virtual image.

12. Multiple Images in Plane Mirrors Two plane mirrors at right angles (90 degrees) produce three images of an object.Two plane mirrors at right angles (90 degrees) produce three images of an object.

13. The Law of Reflection The angle a reflected ray makes with the normal (a perpendicular to the reflecting surface) is equal to the angle that the reflected ray makes with the normal.The angle a reflected ray makes with the normal (a perpendicular to the reflecting surface) is equal to the angle that the reflected ray makes with the normal. The incident ray, normal and reflected ray are all in the same plane.The incident ray, normal and reflected ray are all in the same plane.

14. Curved Mirrors Curved Mirrors are surfaces from a sphere.Curved Mirrors are surfaces from a sphere. Concave mirrors are curved inward.Concave mirrors are curved inward. Convex mirrors are curved outward.Convex mirrors are curved outward. The Centre of Curvature is the centre of the mirror is the centre of the sphere of which the mirror is a part.The Centre of Curvature is the centre of the mirror is the centre of the sphere of which the mirror is a part.

15. Curved Mirror Terms The Vertex (V) is the centre of the mirror.The Vertex (V) is the centre of the mirror. The Principal Axis is the line from the centre of curvature (C) to the vertex.The Principal Axis is the line from the centre of curvature (C) to the vertex. The Focus is the point (halfway between C and V). It is the point that light rays parallel to the principal axis pass through.The Focus is the point (halfway between C and V). It is the point that light rays parallel to the principal axis pass through.

16. Rays Used to Find Images in Curved Mirrors To locate an image, three rays are used.To locate an image, three rays are used. Rays from the object, parallel to the principal axis, reflect back through the focus.Rays from the object, parallel to the principal axis, reflect back through the focus. Rays from the object, passing through the focus, reflect back parallel to the principal axis.Rays from the object, passing through the focus, reflect back parallel to the principal axis. Rays from the object, passing along a line from the centre of curvature, reflect back through the centre of curvature.Rays from the object, passing along a line from the centre of curvature, reflect back through the centre of curvature.

17. Why Rays Parallel to the Principal Axis reflect through the focus. Since the centre of curvature is a normal, constructing an angle of reflection equal to the angle of incidence results in a reflected ray passing through the focus.Since the centre of curvature is a normal, constructing an angle of reflection equal to the angle of incidence results in a reflected ray passing through the focus.

18. The Mirror Formula and Image Features Formula The mirror formula allows the position of an image to be determined.The mirror formula allows the position of an image to be determined. The height and size of the image can be determined using the pinhole camera formula.The height and size of the image can be determined using the pinhole camera formula.

19. Images Formed in Convex Mirrors All images in convex mirrors are virtual images that look like they are behind the mirror because convex mirrors make light rays diverge or spread apart like plane mirror do. Images in convex mirrors are always smaller than the objects.All images in convex mirrors are virtual images that look like they are behind the mirror because convex mirrors make light rays diverge or spread apart like plane mirror do. Images in convex mirrors are always smaller than the objects.

20. Convex Mirror Images Images in convex mirrors are always smaller than the objects. Convex mirrors also give a wider view of the surroundings than a plane mirror.Images in convex mirrors are always smaller than the objects. Convex mirrors also give a wider view of the surroundings than a plane mirror.

21. Concave Mirror Images Concave mirrors can make many different kinds of image, depending on where an object is placed in front of the concave mirror. Most of the images in a concave mirror are real images because concave mirrors converge light rays together.Concave mirrors can make many different kinds of image, depending on where an object is placed in front of the concave mirror. Most of the images in a concave mirror are real images because concave mirrors converge light rays together.

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23. Magnified Images in Concave Mirrors When an object is between the focus and surface of a concave mirror, a larger virtual image forms behind the mirror. Make-up mirrors are concave mirrors.When an object is between the focus and surface of a concave mirror, a larger virtual image forms behind the mirror. Make-up mirrors are concave mirrors.

24. Another Use for a Concave Mirror Because concave mirrors converge light rays to a point, they can be used to focus the energy of light rays to a point to heat up and cook objects.Because concave mirrors converge light rays to a point, they can be used to focus the energy of light rays to a point to heat up and cook objects.

25. Danger With a Concave Mirror ? If a person were to get their eyes on the focus of a concave mirror what danger would there be?If a person were to get their eyes on the focus of a concave mirror what danger would there be?

26. Solar Furnace in Odeillo France The huge concave mirror in Odeillo France focuses light to a spot where the temperatures get to 3500 degrees Celsius.The huge concave mirror in Odeillo France focuses light to a spot where the temperatures get to 3500 degrees Celsius.

27. Summary of Images Formed by a Concave Mirror As an object is brought from a great distance towards a concave mirror, an inverted, smaller real image forms close to the focus. As the object is brought closer, the image (still smaller than the object) gets slightly larger and moves towards the centre of curvature. When the object is at C, the inverted image also forms at C, the same size as the object. As the object moves forward, the image gets larger than the object. Between F and O a larger erect virtual image forms. At F no image forms.

28. Images in a Concave Mirror

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