36. CONCAVE MIRROR
• has the capability of
forming images that can
be smaller or larger in
size and virtual or erect,
depending on the
position of the object.
• always produces a
smaller, virtual, and
erect image of an
• In convex mirror, the
length of the image is
shorter than that of the
39. SW : REFLECTION ON SPHERICAL
½ c.w. DO NOT COPY THE PROBLEM. SHOW COMPLETE SOLUTION
40. 1. A luminous object is 4.00 m from a wall.
You are to use a concave mirror to
project an image of the object on the
wall, with the image 2.25 times the size
of the object. How far should the mirror
be from the wall? What should the
radius of curvature be?
41. 1. Determine the image distance and
image height for a 5.00-cm tall object
placed 20.0 cm from a concave mirror
having a focal length of 15.0 cm.
42. 2. Find the focal length of a convex
mirror of an object 0.30 m from the
mirror forms an image of 0.10 m
behind the mirror.
44. Concave Mirror
• The center C of a concave mirror is outside the
• Focal point F is also outside the mirror, half way
between the center and the surface of the mirror.
• The focal length f is half of the radius.
45. case 1:case 1: The object is placed at a distanceThe object is placed at a distance
greater than the C. The image formed isgreater than the C. The image formed is
real, inverted and smaller in size.real, inverted and smaller in size.
Step 1 Step 2
Step 3 Step 4
46. case 2: The object is placed at a distance
equal to C. The image formed is real,
inverted and the same size as the object.
47. Case 3: The object is placed between C
and f. The image formed is real, inverted
and magnified in size.
64. THIN LENS
• A lens is an optical system with two
• The simplest lens has two spherical
surfaces close enough together that we
can neglect the distance between them
(the thickness of the lens)
66. CONVERGING LENS
• Has the property that when a beam of
rays parallel to the axis passes through
the lens, the rays converge to a point F2
and form a real image at that point.
• Similarly, rays passing through point F1
emerge from the lens as a beam of
• A positive lens (F1 and F2 are both
68. DIVERGING LENS
• The beam of parallel rays incident on
this lens diverges after refraction.
• Is called a negative lens
• The focal length of a diverging lens is
a negative quantity