can any one give the summary of light lesson?
Answers
டேய் மச்சான், நான் உனக்கு Summary தரேன்டா.
Actually, it deals with mirrors and lens.
If the mirror is curved outwards, it is convex. If it is curved inwards, it is concave mirror.
Remember this two definitions,
The centre of reflecting surface is Pole(P)
The reflecting surface forms a part of sphere. the Center of sphere is center of curvature(C).
And a point F called focus.
Then, while mirror reflection the first ray passes through Focus. Second ray passes through C.
Then look at the summary box in your textbook. There Object Position goes front and image position comes back also sizes decreases.
We can say, u is object distance, v is image distance and f is focal length.
In concave, all the three values are negative.
In convex, only u is negative.
In lens, converging lens are convex lens and diverging lens are concave lens.
Comparing to mirror, drawing ray diagram in lens is too easy. In convex, first ray passes parallel to lens and bend to reach F2 and the second ray passes through O as shown in the attachment. the point where two rays coincide, there image will be formed.
Magnification of lens = v/u
Magnification of Mirror = -(v/u)
Power of the lens = 1/f and unit is diopter.(D).
Nothing us much important than this dude.
Score good marks in science
