A "meridian"
a half-circle extending from your horizon due north, through your zenith, to your horizon due south
Its because the rainbow is actually a circle. You only see the segment that goes from horizon to horizon. Sometimes you can see the whole rainbow, even multiple ones around the sun as the light filters through upper level atmosphoric moisture (:
the newton ring
That varies a lot depending on the latitude, from 12 hour day throught Winter and Summer (at the equator), to the Sun being above the horizon all the time, i.e., 24-hour day (in summer, north of the northern polar circle or south of the southern polar circle), or all the time under the horizon, i.e. 0-hour day (in winter, north of the northern polar circle or south of the southern polar circle).That varies a lot depending on the latitude, from 12 hour day throught Winter and Summer (at the equator), to the Sun being above the horizon all the time, i.e., 24-hour day (in summer, north of the northern polar circle or south of the southern polar circle), or all the time under the horizon, i.e. 0-hour day (in winter, north of the northern polar circle or south of the southern polar circle).That varies a lot depending on the latitude, from 12 hour day throught Winter and Summer (at the equator), to the Sun being above the horizon all the time, i.e., 24-hour day (in summer, north of the northern polar circle or south of the southern polar circle), or all the time under the horizon, i.e. 0-hour day (in winter, north of the northern polar circle or south of the southern polar circle).That varies a lot depending on the latitude, from 12 hour day throught Winter and Summer (at the equator), to the Sun being above the horizon all the time, i.e., 24-hour day (in summer, north of the northern polar circle or south of the southern polar circle), or all the time under the horizon, i.e. 0-hour day (in winter, north of the northern polar circle or south of the southern polar circle).
If you mean what you see when you look through a microscope, it is called the field of view. Until you place your eye closer to the eye piece is does appear like a white circle.
its the celestial sphere, Mr. Smith taught me that today, smart man!
This is the diameter of the circle.
This is a line segment called a diameter of the circle.
it can be called the diameter of the circle. or a chord
The line passing through the center of a circle with two endpoints on the circle is the circle's diameter.
International Date Line
It is called a diameter if it goes from end to end and radius if it is half way the circle.
The inside measurement of a circle is called the diameter. It is the distance across the circle, passing through the center.
a diameter
No, a secant line does not pass through the center of a circle. A secant line is a line that intersects a circle in two distinct points. Only a line passing through the center of a circle is called a diameter.
A circle through the Earth's sphere perpendicular to the observer's latitude
That's a diameter of the circle.