IMAGES IN CURVED MIRRORS IMAGES IN CURVED MIRRORS

IMAGES IN CURVED MIRRORS • Concave mirrors are shaped like part of the inside

IMAGES IN CURVED MIRRORS Centre of sphere Concave mirror Convex mirror

The Centre of Curvature ‘C’ is the centre of the sphere of which the

CONCAVE MIRRORS • Rays of light parallel to the principal axis of a mirror,

CONCAVE MIRRORS 1) A light ray parallel to the principal axis is reflected through

1) A light ray parallel to the principal axis is reflected through F C

2) A light ray through C is reflected back onto itself C F

3) A light ray through F will reflect parallel to the principle axis C

4) A light ray aimed at the vertex will follow the Law of Reflection

LOCATING AN IMAGE ON A CONCAVE MIRROR Only two light rays are needed to

LOCATING AN IMAGE ON A CONCAVE MIRROR Object is between F and C of

LOCATING AN IMAGE ON A CONCAVE MIRROR Object is between F and the concave

LOCATING AN IMAGE ON A CONCAVE MIRROR There are three regions where an object

CONVEX MIRRORS • In a convex mirror, rays of light (parallel to the principal

CONVEX MIRRORS 1) A ray parallel to the principal axis is reflected as if

1) A ray parallel to the principal axis is reflected as if it had

2) A ray aimed at C is reflected back upon itself F C

3) A ray aimed at F is reflected parallel to the principal axis F

LOCATING AN IMAGE ON A CONVEX MIRROR Only two light rays are needed to

LOCATING AN IMAGE ON A CONVEX MIRROR The image of an object in a

Slides: 34

Download presentation

IMAGES IN CURVED MIRRORS

IMAGES IN CURVED MIRRORS • Concave mirrors are shaped like part of the inside of a sphere • Convex mirrors are shaped like part of the outside of a sphere

IMAGES IN CURVED MIRRORS Centre of sphere Concave mirror Convex mirror

The Centre of Curvature ‘C’ is the centre of the sphere of which the curved mirror forms a part. The Pole ‘P’ is the midpoint of the mirror (a. k. a. vertex) The Principal Axis is the straight line passing through the pole and the centre of curvature of a spherical mirror. The Normal at any point of a curved mirror is the straight line joining that point with the centre of curvature C of the mirror.

CONCAVE MIRRORS

CONCAVE MIRRORS • Rays of light parallel to the principal axis of a mirror, reflect through a point (in case of a concave mirror) on the principal axis. This point is the focus or focal point ‘f’ of the mirror. • A concave mirror is also known as a converging mirror • The focus is in front of the mirror. • The focus is real as the rays of light after reflection converge at the focus.

CONCAVE MIRRORS 1) A light ray parallel to the principal axis is reflected through F 2) A light ray through C is reflected back onto itself 3) A light ray through F will reflect parallel to the principle axis 4) A light ray aimed at the vertex will follow the Law of Reflection (angle of incidence = angle of reflection)

1) A light ray parallel to the principal axis is reflected through F C F

2) A light ray through C is reflected back onto itself C F

3) A light ray through F will reflect parallel to the principle axis C F

4) A light ray aimed at the vertex will follow the Law of Reflection (angle of incidence = angle of reflection) C F V

LOCATING AN IMAGE ON A CONCAVE MIRROR Only two light rays are needed to locate an image 1) A light ray parallel to the principal axis is reflected through F 2) A light ray through C is reflected back onto itself 3) A light ray through F will reflect parallel to the principle axis 4) A light ray aimed at the vertex will follow the Law of Reflection (angle of incidence = angle of reflection)

LOCATING AN IMAGE ON A CONCAVE MIRROR

LOCATING AN IMAGE ON A CONCAVE MIRROR Object is between F and C of a concave mirror: • the image is larger than the object • the image is inverted • the image is farther from the mirror than the object is • the image is real

LOCATING AN IMAGE ON A CONCAVE MIRROR

LOCATING AN IMAGE ON A CONCAVE MIRROR Object is between F and the concave mirror: • the image is larger than the object • the image is upright • the image is behind the mirror • the image is virtual i. e. makeup mirrors

LOCATING AN IMAGE ON A CONCAVE MIRROR There are three regions where an object can be located: • beyond C • between C and F • between the mirror and F

CONVEX MIRRORS

CONVEX MIRRORS • In a convex mirror, rays of light (parallel to the principal axis of a mirror), appear to diverge from a point on the principal axis. This point is the focus or focal point ‘f’ of the mirror. • A convex mirror is also known as a diverging mirror • The focus is behind the mirror • The focus is virtual as the rays of light after reflection appear to come from the focus behind the mirror

CONVEX MIRRORS 1) A ray parallel to the principal axis is reflected as if it had come through F 2) A ray aimed at C is reflected back upon itself 3) A ray aimed at F is reflected parallel to the principal axis

1) A ray parallel to the principal axis is reflected as if it had come through F F C Any lines past a mirror are NOT light rays. They are represented as dotted lines.

2) A ray aimed at C is reflected back upon itself F C

3) A ray aimed at F is reflected parallel to the principal axis F C

LOCATING AN IMAGE ON A CONVEX MIRROR Only two light rays are needed to locate an image 1) A ray parallel to the principal axis is reflected as if it had come through F 2) A ray aimed at F is reflected parallel to the principal axis

LOCATING AN IMAGE ON A CONVEX MIRROR

LOCATING AN IMAGE ON A CONVEX MIRROR The image of an object in a convex mirror will have the following characteristics: • the image is smaller than the object • the image is upright • the image is closer to the mirror than the object is • the image is virtual The images in convex mirrors are much more similar to each other than those in concave mirrors.