Tangent Line Discovery

Rotate the straight wire around point P to discover when it becomes a tangent to the circle

Wire Rotation Controls

45° 360°
Slow Fast

Move Point P:

💡 Tip: You can also drag point P directly on the circle!

🔍 Keep rotating: Watch how the second intersection point Q moves closer to P as you approach the tangent position.

Observations

Intersection Points

2
points where wire meets circle

Line Type

Secant Line
current classification

Distance Q to P

0.000
units (approaches 0 for tangent)

Understanding Tangents

1

Secant Line: A line that intersects a circle at two distinct points.

2

Tangent Line: A special case where the line touches the circle at exactly one point.

3

Key Discovery: There is only one tangent line possible at any given point on a circle, and it's always perpendicular to the radius at that point.

4

Interactive Tip: Drag point P around the circle to explore tangent lines at different positions!