# lens

sign convention is very important. for which i have shared this note. Following sign convention is used for measuring various distances during the formation of images by lenses:

All distances on the principal axis are measured from the optical center. The distances measured in the direction of incident rays are positive and all the distances measured in the direction opposite to that of the incident rays are negative. All distances measured above the principal axis are positive. Thus, height of an object and that of an erect image are positive and all distances measured below the principal axis are negative. The following table gives the sign convention for lenses:

Type of lens u v f Height of the image (hI) Height of the object (hO) Real Virtual Real Virtual Real Virtual
Convex - + - + No virtual focus - + + Concave - No real image is formed - No real focus - No real image is formed + +

Note by Mirtaki Tajwar
4 years ago

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold
- bulleted- list
• bulleted
• list
1. numbered2. list
1. numbered
2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears as
Remember to wrap math in $$...$$ or $...$ to ensure proper formatting.
2 \times 3 $$2 \times 3$$
2^{34} $$2^{34}$$
a_{i-1} $$a_{i-1}$$
\frac{2}{3} $$\frac{2}{3}$$
\sqrt{2} $$\sqrt{2}$$
\sum_{i=1}^3 $$\sum_{i=1}^3$$
\sin \theta $$\sin \theta$$
\boxed{123} $$\boxed{123}$$

Sort by:

THANKYOU .

- 3 years, 6 months ago