Length or distance between two points.
It is called the distance between the points. A common one is the Pythagorean distance but there are many other measures.
The distance between one point of a wave to the same point on the next wave is called the wavelength.
That is called the "wavelength".
That is incorrect.The distance of one complete wave cycle (for example, from one wave crest to the next) is called the wave's wavelength.The number of cycles per second is called the frequency.
That is called its' wavelength. From a selected point to the next similar point. Peak to peak for example.
there are 3 measurements of a circle the diameter, which is the distance from one point of the circle through the center point to the other side the radius, which is the distance from the center point to any point of the circle (which is 1/2 of the diameter) and the circumference, which is the distance from one point on the circle all the way around to the point you started at
The distance through the center of a circle is called the diameter.
Distance.
wavelength
The distance between successive identical parts of a wave is called the wave length.
No, neither. The radius is the distance from the center point of a circle to its edge. The diameter is the distance from one edge to the other that passes through the center point. The diameter is therefore twice the radius.
The distance from crest to crest (or trough to trough) is the wavelength.