1. 4.4 Images in Curved Mirrors

2. Types of Curved Mirrors:
Concave:
Inner surface of curved mirror is reflective
Convex:
Outer surface of curved mirror is reflective

3. Terminology Centre of Curvature (C) Principal Axis (PA) Vertex (V)
Centre of the sphere whose surface is used to make the mirror
Principal Axis (PA)
Line going through the centre of curvature and the centre of the mirror
Vertex (V)
Point where the
principal axis intersects the mirror

4. Focus (F) The point where parallel light rays come together
on a concave mirror. It is exactly halfway between C and V.

5. Real Image
An image that can be seen on a screen as a result of light rays actually arriving at that particular location
Video- Vital Science: Curved Mirrors

7. Locating Images in Converging (Concave) Mirrors
Draw two incident light rays from the top of the object
1. One parallel to the PA, then reflects through F
2. One through C, then reflects back upon itself
The point where the two reflected rays intersect is where the image will form
NOTE: you could use all four types of incident rays but only two are needed for a point of intersection

8. Object beyond C
S- smaller
A- inverted L- b/t F and C
T- real

9. Object at C
S- same
A- inverted L- at C
T- real S-
A- L- T-

10. Object between F and C S- larger A- inverted L- beyond C T- real S-

11. Object at F
-cannot run a ray through the focal point so run one through the centre of curvature
Reflected rays do not intersect as they are parallel.
*no clear image forms* S- A- L- T-

12. Object between V and F -extend reflected rays back behind mirror
S- larger
A- upright L- behind mirror
T- virtual

13. Convex Mirror
Light rays DIVERGE on the mirror and meet at a VIRTUAL FOCUS behind the mirror
Large viewing area but can cause some distortion
Used to view large areas like in a variety store
Produce smaller upright virtual images

14. Reflection of a Convex Mirror
A ray parallel to the PA is reflected as if it had come through the focus
A ray aimed at the focus will reflect back parallel to the PA
A ray aimed at the centre of curvature is reflected back upon itself

15. S - smaller
A – upright
L – behind mirror
T- virtual
Object will always be in front of mirror and therefore image will ALWAYS be smaller, upright, behind mirror and virtual

17. F C V