Hansen , Trevin , Meiga , Carissa

CONVEX LENS

IMMANUEL CHRISTIAN SCHOOL (SENIOR HIGH) BILINGUAL CLASS

GRADE X 2012-2013

What is Convex lens??

Transparent mediumUsed in toolsHipermethropy (near-sighted)

CONVEX & CONCAVE LENS

SPECIAL RAYS

2F1 F1 F2 2F2

2F1 F1 F2 2F2

Between focal point and the lens

2F1 F1 F2 2F2

Between 2F1 and F1

2F1 F1 F2 2F2

Beyond 2f

Object positio

n

Image positio

n

Larger, smaller, or same

size?

Upright or

inverted?

Virtual or real ?

Between F and the lens

Between F and

2F1

larger upright Virtual

Between 2F

and F

More than 2F2

Larger Inverted Real

Beyond 2F

Between F2 and 2F2

smaller Inverted Real

Convex lens

Note:f = focal length (+)S = object distanceS’ = image distance

1𝑓=1𝑆 ′

+1𝑆

A. Relations between object lengths and image lengths

𝑀=|h′h |=|𝑠 ′𝑠 |Note :M = magnificationh = height objecth’ = height images = object distances’ = image distance

B. Image magnification

e.gA convex lens has 20 cm of focal length. With the object placed 10 cm in front of the lens. Determine the image position , the magnification, and the characteristics of the image of an object.

POWER OF LENS

Examples:

Q: the focal length of a convex lens is 5 cm. What is the optical power of lens?

History of formulaa

2F1 F1 F2 2F2

1𝑓=1𝑆 ′

+1𝑆

The focal length of a convex lens is 12 cm. An object is placed in front of the lens, Determine :a.) The image lengthb.) The magnification of the imagec.) The power of lensd.) Ray diagrame.) The size of the image if the object size is 12 cm

Q :RECALLING

An object with 5 cm in height is put in front of a converging lens.The image formed is located 12 cm behind the lens and it is 15 cm in height. Find the power of lens. And draw the diagram.

THANK YOU