Question

define the following term:
A) -focal length
B) - aperture
C) - pole

Answer 1

focal length-the distance between the centre of a lens or curved mirror and its focus

aperture-a space through which light passes in an optical or photographic instrument, especially the variable opening by which light enters a camera

pole-It is the center of the reflecting surface of the mirror

Answer 2

A) focal length is the distance between the pole of the mirror (centre of the lens or mirror) and the Principal Focus.

B) aperture is the entire reflecting surface.

C) pole is the center of the reflecting surface.