This presentation would cover Rules for tracing images formed by concave mirror, Image formation by a concave mirror in different positions of the object and Summary of the characteristics of images formed by a concave mirror

1. LEARNING OBJECTIVES—VIDEO 3
•RULES FOR TRACING IMAGES FORMED BY
CONCAVE MIRROR.
•IMAGE FORMATION BY A CONCAVE MIRROR
IN DIFFERENT POSITIONS OF THE OBJECT.
•SUMMARY OF THE CHARACTERISTICS OF
IMAGES FORMED BY A CONCAVE MIRROR.

2. RULES FOR TRACING IMAGE BY CONCAVE MIRRORS
• When an object is placed in front of a concave mirror .its image is formed
by reflection in the mirror.
• Every point on the object acts like a point source, from which an infinite
number of rays originate.
• For the sake of simplicity, we take any two rays of light whose paths on
reflection from the mirror are known to us .

3. RULES FOR CONCAVE MIRROR
• RULE 1: A ray of light falling on a concave mirror in a direction parallel to
the principal axis of the mirror, passes actually through the principal focus
F of the mirror, on reflection from the mirror.

4. RULES FOR CONCAVE MIRROR
• RULE 2: A ray of light incident on a concave mirror on passing through
centre of curvature C of the mirror is reflected back along the same path i.e.
such a ray retraces its path in opposite direction.

5. RULES FOR CONCAVE MIRROR
• RULE 3: A ray of light incident on a concave mirror on passing through
focus F of the mirror becomes parallel to principal axis of the mirror, on
reflection.

6. RULES FOR CONCAVE MIRROR
• RULE 4: A ray of light incident obliquely towards the pole P of concave
mirror is reflected obliquely as per the laws of reflection.

7. IMAGE FORMATION BY CONCAVE MIRROR IN DIFFERENT CASES
• The type of image formed by the
concave mirror depends on position of
object in front of the mirror.
• CASE 1: When object is at infinity
(large distance)
• Image is—
• i)Formed at the principal focus F.
• ii) Real and inverted.
• iii)Much smaller in size than the object.

8. OBJECT AT INFINITY

9. IMAGE FORMATION BY CONCAVE MIRROR
• CASE 2: When the object is beyond the centre of curvature of concave
mirror.
• Image is –
• Real and inverted.
• Smaller in size than the object.
• Lying between the F and C of the mirror.

10. IMAGE FORMATION BY CONCAVE MIRROR
• CASE 3: When the object is at the centre of curvature of concave mirror.
• Image is ---
• Real and inverted.
• At the centre of curvature of the mirror.
• Of the same size as the object.

11. IMAGE FORMATION BY CONCAVE MIRROR
• CASE 4: When the object lies between centre of curvature C and focus F of
concave mirror.
• Image is ---
• Real and inverted.
• Larger in size than the object.
• Situated beyond C.

12. IMAGE FORMATION BY CONCAVE MIRROR
• CASE 5: When the object is at the focus F of a concave mirror.
• Image is –
• At infinity.
• Real and inverted.
• Highly enlarged or magnified.

13. IMAGE FORMATION BY CONCAVE MIRROR
• CASE 6: When the object is held between focus F and pole P of the
concave mirror.
• Image is –
• Virtual and erect.
• Larger than the size of the object.
• Behind the mirror.

15. SUMMARY
• RULES FOR TRACING IMAGES FORMED BY CONCAVE MIRROR.
• IMAGE FORMATION BY A CONCAVE MIRROR IN DIFFERENT
POSITIONS OF THE OBJECT.
• SUMMARY OF THE CHARACTERISTICS OF IMAGES FORMED BY
A CONCAVE MIRROR.