Question

Define focal length​

Answer 1

Answer:

The distance between the pole P of the concave mirror and the focus F is the focal length of the concave mirror

Answer 2

Answer:

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Explanation:

Question:

Define focal length.

Definition:

$\implies$ The distance between the pole and the principal focus of a spherical mirror is called the focal length.

Representation:

$\implies$ It is represented by the letter $\textit{f}$