3.2 Images formed by a convex lens

1. Preparation - Chapter 3.2a, Chapter 3.2b, Chpater 3.2c, Chapter 3.2d

2. Participation - Assignment P.100 Q7-11 <Assignment 3>

3. Presentation - Blackboard, Student's Work

4. Possession
   > Convex lens may form "real and inverted image" or "erect and virtual image".
   > Do an experiment to show how a convex lens form images of different natures.
   > Real images can be projected on a screen.
   > Virtual images can never be projected on a screen
   > Images can be magnified or diminished.
   > Apply construction rules for a convex lens to show formation of images.
   > Using construction rules, draw the refracted ray when a light ray incident on a convex lens and the ray does not passes through the centre.
   > A light ray passes through 2F on one side of a convex lens should also pass through the 2F on the opposite side.
   > Complete an incomplete ray diagram. (e.g. P.90, ray s)
   > Identify natures of image in photos (P.93) as well as magnification (P.95 Fig. a)
   > A opaque card in front of a lens reduces the brightness of an image.
   > A larger convex lens collects more light, the image is brighter. (P.122 Q34b)
   > Using the same lens, a smaller image is brighter as light energy is more concentrated.
   > Apply lens formula, image distance of virtual image is NEGATIVE.
   > Vocabulary: translucent screen, diminished 

3.3 Images formed by a concave lens

1. Preparation - Chapter 3.3a, Chapter 3.3b, Chapter 3.3c

2. Participation - Assignment ...
   P.113 Q4-7 and P.121 Q26-31 <Assignment 4> and
   P.121 Q34-39 and 41 <Assignment 5>

3. Presentation - Blackboard, Student's Work

4. Possession
   > Concave lens may form "erect, virtual and diminished image" only.
   > Do an experiment to show how a concave lens form image.
   > Apply construction rules for a concave lens to show formation of images.
   > Using construction rules, draw the refracted ray when a light ray incident on a convex lens and the ray does not passes through the centre.
   > Complete an incomplete ray diagram. (e.g. P.106, ray s)
   > Identify natures of image in photos (P.107) as well as magnification (P.112 Fig. a)
   > A opaque card in front of a lens reduces the brightness of an image.
   > A larger concave lens collects more light, the image is brighter. (P.122 Q34b)
   > Using the same lens, a smaller image is brighter as light energy is more concentrated.
   > Apply lens formula.  Focal length of concave lens is NEGATIVE!  Also, image distance of virtual image is NEGATIVE.