Question

what is the eccentricity of a perfect circle?

Explanation:

Step1: Recall the formula for eccentricity

The formula for the eccentricity \(e\) of a conic section is \(e=\frac{c}{a}\). For a circle, \(c = 0\) (where \(c\) is the distance from the center to the focus and \(a\) is the semi - major axis).

Step2: Calculate the eccentricity of a circle

Substitute \(c = 0\) into the formula \(e=\frac{c}{a}\). We get \(e=\frac{0}{a}\), and since \(a>0\) (for a non - degenerate circle), \(e = 0\).

Answer:

C. 0