Question

The distances between the dash and the focus is called the focal length

PLEASE ANSWER THIS QUESTION CORRECTLY​

Answer 1

Answer:

The answer is Focal length. The distance between the optic centre of a lens and its principal focus is called Focal Length. The principal focus is the point on the principal axis where all the rays pass through after refracting from the lens when the rays are travelling parallel to the principal axis.

Answer 2

Answer:

The focal length of an optical system is a measure of how strongly the system converges or diverges light.

hope it will help u

if not sorry