Question

What is the focal length of a
lens.​

Answer 1

Answer:

Hope it hepls you :)

Explanation:

The focal length of the lens is the distance between the lens and the image sensor when the subject is in focus, usually stated in millimeters (e.g., 28 mm, 50 mm, or 100 mm).

Answer 2

Answer:

➡ ᴛʜᴇ ᴅɪsᴛᴀɴᴄᴇ ᴏғ ғᴏᴄᴜs (ᴏʀ ғᴏᴄᴀʟ ᴘᴏɪɴᴛ) ғʀᴏᴍ ᴛʜᴇ ᴏᴘᴛɪᴄᴀʟ ᴄᴇɴᴛʀᴇ ᴏғ ᴀ ʟᴇɴs , ɪs ᴄᴀʟʟᴇᴅ ɪᴛ's ғᴏᴄᴀʟ ʟᴇɴɢᴛʜ. ᴀ ʟᴇɴs ʜᴀs ᴛᴡᴏ ғᴏᴄᴀʟ ʟᴇɴɢᴛʜs.

i)- ғɪʀsᴛ ғᴏᴄᴀʟ ʟᴇɴɢᴛʜ

ii)- sᴇᴄᴏɴᴅ ғᴏᴄᴀʟ ʟᴇɴɢᴛʜ