Y Axis
The y-axis is the vertical number line in a Cartesian coordinate system that intersects the horizontal x-axis at a right angle. The point where these two axes intersect is called the origin. It is used to measure the vertical position, known as the ordinate, of a point in a two-dimensional plane.
Key Concepts
Every point located exactly on the y-axis has an x-coordinate, or abscissa, of zero, meaning its coordinates are always in the form (0, y).
The y-axis divides the Cartesian plane into left and right halves, with positive values extending upwards from the origin and negative values extending downwards.
The perpendicular distance of any point (x, y) from the y-axis is determined by the absolute value of its x-coordinate.
Real World Applications
The vertical shaft of an elevator in a high-rise building, where the ground floor is the origin and floors above and below represent positive and negative y-values.
Measuring the altitude of an airplane or the depth of a submarine relative to sea level on a two-dimensional radar screen.