Slide 1

  • Topic: Optics - Reflection of Light and Formation of Images
  • Subtopic: Reflection of Arbitrary Ray

Slide 2

  • Recap of Basics:
    • Light is an electromagnetic wave.
    • Reflection occurs when light bounces off a surface.
    • Incident ray, reflected ray, and the normal all lie in the same plane.

Slide 3

  • Importance of Reflection:
    • Reflection helps us see objects.
    • We use reflections for various applications like mirrors, lenses, etc.
    • Understanding reflection is essential for studying optics.

Slide 4

  • Laws of Reflection:
    1. The incident ray, the reflected ray, and the normal at the point of incidence, all lie in the same plane.
    2. The angle of incidence is equal to the angle of reflection.
  • These laws apply to all types of reflections.

Slide 5

  • Incident Ray: The ray of light that strikes a surface.
  • Reflected Ray: The ray of light that bounces off the surface after reflection.
  • Angle of Incidence: The angle between the incident ray and the normal at the point of incidence.
  • Angle of Reflection: The angle between the reflected ray and the normal at the point of incidence.

Slide 6

  • Ray Diagram:
    1. Draw a straight line representing the surface of reflection.
    2. Mark a point on this line representing the point of incidence.
    3. Draw the incident ray and the reflected ray, making the angles of incidence and reflection as shown.

Slide 7

  • Examples of Reflection:
    1. Reflection from a Plane Mirror:
      • The angle of incidence is equal to the angle of reflection.
      • The reflected ray appears to come from behind the mirror.
    2. Reflection from a Spherical Mirror:
      • Depends on the curvature of the mirror.
      • Can form different types of images.

Slide 8

  • Law of Reflection Equation:
    • Angle of Incidence (θi) = Angle of Reflection (θr)
  • Mathematically expressed as: θi = θr
  • This equation holds for all types of reflections.

Slide 9

  • Incident Ray and Reflected Ray:
    • Incident ray and reflected ray are on opposite sides of the normal.
    • Incident ray, reflected ray, and normal all lie in the same plane.
  • Visual representation for a better understanding.

Slide 10

  • Summary of Reflection:
    1. Reflection occurs when light bounces off a surface.
    2. The laws of reflection state that the incident ray, reflected ray, and the normal lie in the same plane, and the angles of incidence and reflection are equal.
    3. Reflection is crucial for various applications in optics.

Slide 11

  • Recap of Basics:
    • Light is an electromagnetic wave.
    • Reflection occurs when light bounces off a surface.
    • Incident ray, reflected ray, and the normal all lie in the same plane.
  • Incident Ray and Reflected Ray:
    • Incident ray and reflected ray are on opposite sides of the normal.
    • Incident ray, reflected ray, and normal all lie in the same plane.
  • Examples of Reflection:
    1. Reflection from a Plane Mirror:
      • The angle of incidence is equal to the angle of reflection.
      • The reflected ray appears to come from behind the mirror.
    2. Reflection from a Spherical Mirror:
      • Depends on the curvature of the mirror.
      • Can form different types of images.

Slide 12

  • Laws of Reflection:
    1. The incident ray, the reflected ray, and the normal at the point of incidence, all lie in the same plane.
    2. The angle of incidence is equal to the angle of reflection.
  • These laws apply to all types of reflections.
  • Law of Reflection Equation:
    • Angle of Incidence (θi) = Angle of Reflection (θr)
    • Mathematically expressed as: θi = θr

Slide 13

  • Reflection in Plane Mirrors:
    • Plane mirrors are flat reflecting surfaces.
    • When light falls on a plane mirror, it reflects in a regular manner.
    • The image formed is virtual, upright, and of the same size as the object.
    • The distance of the image from the mirror is equal to the distance of the object from the mirror.
    • Example: Reflection in a bathroom mirror.
  • Ray Diagram for Reflection in Plane Mirror:
    • Draw the incident ray, reflected ray, and the normal on the mirror.

Slide 14

  • Reflection in Spherical Mirrors:
    • Spherical mirrors have curved reflecting surfaces.
    • Two types of spherical mirrors:
      1. Concave Mirror: Reflects light inwards, forms real or virtual images depending on object position.
      2. Convex Mirror: Reflects light outwards, forms virtual images only.
  • Ray Diagram for Reflection in Spherical Mirrors:
    • Draw the incident ray, reflected ray, and the normal on the mirror.
    • Determine the focus, center of curvature, and radius of curvature for the particular mirror.

Slide 15

  • Sign Convention for Spherical Mirrors:
    • Concave Mirror:
      • When an object is placed beyond the center of curvature, the image is real, inverted, and smaller in size.
      • When an object is placed between the center of curvature and the focus, the image is real, inverted, and magnified.
      • When an object is placed at the focus, the reflected rays become parallel, and no real image is formed.
      • When an object is placed between the pole and focus, the image is virtual, erect, magnified, and on the same side as the object.

Slide 16

  • Sign Convention for Spherical Mirrors:
    • Convex Mirror:
      • The image formed is always virtual, erect, and diminished in size.
      • The image is formed behind the mirror, on the same side as the object.
      • The image cannot be obtained on a screen.
  • Ray Diagram for Convex Mirror:
    • Draw the incident ray, reflected ray, and the normal on the mirror.
    • Show the virtual image formed behind the mirror.

Slide 17

  • Mirror Formula:
    • The mirror formula relates the object distance (u), image distance (v), and the focal length (f) of a mirror.
    • The formula is given by:
      • 1/f = 1/v - 1/u
  • Magnification Equation:
    • The magnification (m) of an image formed by a mirror is given by:
      • m = -v/u
  • These equations help determine the characteristics of the image formed by a mirror.

Slide 18

  • Lens and Lens Terminology:
    • A lens is a transparent material with at least one curved surface.
    • Two types of lenses:
      1. Convex Lens: Thicker at the center, converges light rays to a point.
      2. Concave Lens: Thinner at the center, diverges light rays.
  • Lens Terminology:
    • Optical Center: The midpoint of the lens.
    • Principal Axis: A line passing through the center of curvature and the optical center.
    • Focus: The point where parallel rays converge or appear to diverge from.

Slide 19

  • Formation of Images by Lenses:
    • Convex Lens:
      • Forms real, inverted, and diminished images when the object is placed beyond the focus.
      • Forms virtual, erect, and magnified images when the object is placed between the focus and the lens.
    • Concave Lens:
      • Always forms virtual, upright, and diminished images.
      • Images formed are always on the same side as the object.
  • Ray Diagrams for Lenses:
    • Draw the incident ray, refracted ray, and the normal on the lens.
    • Determine the position of the image and its characteristics.

Slide 20

  • Lens Formula:
    • The lens formula relates the object distance (u), image distance (v), and the focal length (f) of a lens.
    • The formula is given by:
      • 1/f = 1/v - 1/u
  • Magnification by a Lens:
    • The magnification (m) of an image formed by a lens is given by:
      • m = -v/u
  • These equations help determine the characteristics of the image formed by a lens.

Slide 21

  • Recap of Basics:
    • Light is an electromagnetic wave.
    • Reflection occurs when light bounces off a surface.
    • Incident ray, reflected ray, and the normal all lie in the same plane.
  • Incident Ray and Reflected Ray:
    • Incident ray and reflected ray are on opposite sides of the normal.
    • Incident ray, reflected ray, and normal all lie in the same plane.
  • Examples of Reflection:
    1. Reflection from a Plane Mirror:
      • The angle of incidence is equal to the angle of reflection.
      • The reflected ray appears to come from behind the mirror.
    2. Reflection from a Spherical Mirror:
      • Depends on the curvature of the mirror.
      • Can form different types of images.

Slide 22

  • Laws of Reflection:
    1. The incident ray, the reflected ray, and the normal at the point of incidence, all lie in the same plane.
    2. The angle of incidence is equal to the angle of reflection.
  • These laws apply to all types of reflections.
  • Law of Reflection Equation:
    • Angle of Incidence (θi) = Angle of Reflection (θr)
    • Mathematically expressed as: θi = θr
  • Incident Ray and Reflected Ray:
    • Incident ray and reflected ray are on opposite sides of the normal.
    • Incident ray, reflected ray, and normal all lie in the same plane.

Slide 23

  • Reflection in Plane Mirrors:
    • Plane mirrors are flat reflecting surfaces.
    • When light falls on a plane mirror, it reflects in a regular manner.
    • The image formed is virtual, upright, and of the same size as the object.
    • The distance of the image from the mirror is equal to the distance of the object from the mirror.
    • Example: Reflection in a bathroom mirror.
  • Ray Diagram for Reflection in Plane Mirror:
    • Draw the incident ray, reflected ray, and the normal on the mirror.

Slide 24

  • Reflection in Spherical Mirrors:
    • Spherical mirrors have curved reflecting surfaces.
    • Two types of spherical mirrors:
      1. Concave Mirror: Reflects light inwards, forms real or virtual images depending on the object’s position.
      2. Convex Mirror: Reflects light outwards, forms virtual images only.
  • Ray Diagram for Reflection in Spherical Mirrors:
    • Draw the incident ray, reflected ray, and the normal on the mirror.
    • Determine the focus, center of curvature, and radius of curvature for the particular mirror.

Slide 25

  • Sign Convention for Spherical Mirrors:
    • Concave Mirror:
      • When an object is placed beyond the center of curvature, the image is real, inverted, and smaller in size.
      • When an object is placed between the center of curvature and the focus, the image is real, inverted, and magnified.
      • When an object is placed at the focus, the reflected rays become parallel, and no real image is formed.
      • When an object is placed between the pole and focus, the image is virtual, erect, magnified, and on the same side as the object.
  • Sign Convention for Spherical Mirrors:
    • Convex Mirror:
      • The image formed is always virtual, erect, and diminished in size.
      • The image is formed behind the mirror, on the same side as the object.
      • The image cannot be obtained on a screen.
  • Ray Diagram for Convex Mirror:
    • Draw the incident ray, reflected ray, and the normal on the mirror.
    • Show the virtual image formed behind the mirror.

Slide 26

  • Mirror Formula:
    • The mirror formula relates the object distance (u), image distance (v), and the focal length (f) of a mirror.
    • The formula is given by:
      • 1/f = 1/v - 1/u
  • Magnification Equation:
    • The magnification (m) of an image formed by a mirror is given by:
      • m = -v/u
  • These equations help determine the characteristics of the image formed by a mirror.

Slide 27

  • Lens and Lens Terminology:
    • A lens is a transparent material with at least one curved surface.
    • Two types of lenses:
      1. Convex Lens: Thicker at the center, converges light rays to a point.
      2. Concave Lens: Thinner at the center, diverges light rays.
  • Lens Terminology:
    • Optical Center: The midpoint of the lens.
    • Principal Axis: A line passing through the center of curvature and the optical center.
    • Focus: The point where parallel rays converge or appear to diverge from.
  • Formation of Images by Lenses:
    • Convex Lens:
      • Forms real, inverted, and diminished images when the object is placed beyond the focus.
      • Forms virtual, erect, and magnified images when the object is placed between the focus and the lens.

Slide 28

  • Formation of Images by Lenses (Continued):
    • Concave Lens:
      • Always forms virtual, upright, and diminished images.
      • Images formed are always on the same side as the object.
  • Ray Diagrams for Lenses:
    • Draw the incident ray, refracted ray, and the normal on the lens.
    • Determine the position of the image and its characteristics.
  • Lens Formula:
    • The lens formula relates the object distance (u), image distance (v), and the focal length (f) of a lens.
    • The formula is given by:
      • 1/f = 1/v - 1/u

Slide 29

  • Lens Formula (Continued):
    • Magnification by a Lens:
      • The magnification (m) of an image formed by a lens is given by:
        • m = -v/u
  • These equations help determine the characteristics of the image formed by a lens.
  • Recap of the Topic:
    • Reflection is the bouncing back of light when it strikes a surface.
    • The laws of reflection state that the incident ray, reflected ray, and the normal all lie in the same plane, and the angles of incidence and reflection are equal.
    • Plane mirrors form virtual, upright images of the same size as the object.
    • Spherical mirrors and lenses can form real or virtual images depending on the object’s position.

Slide 30

  • Summary:
    • Reflection occurs when light bounces off a surface.
    • The laws of reflection state that the incident ray, the reflected ray, and the normal at the point of incidence all lie in the same plane, and the angle of incidence is equal to the angle of reflection.
    • Plane mirrors form virtual, upright images of the same size as the object.
    • Spherical mirrors and lenses can form real or virtual images depending on the object’s position.
    • Lens and mirror formulas help determine the characteristics of the image formed.
  • Thank you for your attention!