Read More
Date: 3-6-2019
1902
Date: 30-3-2019
1762
Date: 19-9-2019
1438
|
Arc length is defined as the length along a curve,
(1) |
where is a differential displacement vector along a curve . For example, for a circle of radius , the arc length between two points with angles and (measured in radians) is simply
(2) |
Defining the line element , parameterizing the curve in terms of a parameter , and noting that is simply the magnitude of the velocity with which the end of the radius vector moves gives
(3) |
In polar coordinates,
(4) |
so
(5) |
|||
(6) |
In Cartesian coordinates,
(7) |
|||
(8) |
|||
(9) |
|||
(10) |
Therefore, if the curve is written
(11) |
then
(12) |
If the curve is instead written
(13) |
then
(14) |
In three dimensions,
(15) |
so
(16) |
The arc length of the polar curve is given by
(17) |
|
|
علامات بسيطة في جسدك قد تنذر بمرض "قاتل"
|
|
|
|
|
أول صور ثلاثية الأبعاد للغدة الزعترية البشرية
|
|
|
|
|
مكتبة أمّ البنين النسويّة تصدر العدد 212 من مجلّة رياض الزهراء (عليها السلام)
|
|
|