the answer is a Tangent.
Acceleration is the derivative of velocity (a=dv/dt). If you are not familiar with calculus then it would be sufficient to say that the slope of the line tangent to the graph, only touches at one point, is equal to the instantaneous acceleration.
With respect to the earth itself (disregarding the earth's orbital displacement during a rotation), it forms a circle or, more specifically, a line of latitude.
The equator is an imaginary line. It therefore does not touch anything
-- Since every point on a line of latitude has the same latitude, the line has no thickness. -- Its length depends on its latitude. -- The line at zero latitude, known as the 'equator', is a great circle and so its length is the circumference of the Earth ... about 24,900 miles. -- Every other line of latitude is a small circle. Its length is 24,900 miles times the cosine of the latitude which it marks. -- The distance between any latitude and the one that's 1° north or south of it is about 111.1 kilometers (69 miles).
The equator is the longest line of latitude as it is located at the circumference of Earth, and the circumference of Earth is always the longest compared to anywhere as the theory is the same of the circumference of a sphere.
A tangent of a circle is a straight line that touches the circle at only one point.
A tangent line touches the circumference of a circle at just one point but it does not intersect the circle.
A tangent line touches the circumference of a circle exactly at one point.
A tangent.
A tangent is a straight line that touches a circle's circumference at one point
a tangent is a line that touches the circle at only ONE point
Such a line is called a tangent line or a tangent to the circle. [Tangent is Latin for touching-- a tangent line touches the circle at just one point. ]
Is calleda tangent line. Is called a tangent line
A tangent of a circle is a straight line that touches the circle's circumference at just one point
A tangent of a circle is a straight line that touches the circle's circumference at just one point.
tangent
A tangent is a straight line that touches the outer circumference of a circle at one point