Question

what is principal focus of a lens​

Answer 1

A principal focus or focal point is a special focus: For a lens, or a spherical or parabolic mirror, it is a point onto which collimated light parallel to the axis is focused.

Since light can pass through a lens in either direction, a lens has two focal points – one on each side.

$<b><marquee>$Mark me as brainliest please

Answer 2

Answer:

dear ur answer is in this attachment please kindly refer to the attachment and please mark me as brainlist and pls follow me dear