Question

two thin lenses of focal length f1 and f2 are placed adjacent to each other. what is the focal length of the combination

Answer 1

Answer:

Hope it helps you

Explanation:

For the lenses placed coaxially, We have the relationship P = P1 + P2 + P3 + . So,for given case P = P1 + P2 or P = 1f1 + 1f2

Answer 2

Answer:

➡ ᴛʜᴇ ᴅɪsᴛᴀɴᴄᴇ ᴏғ ғᴏᴄᴜs ғʀᴏᴍ ᴛʜᴇ ᴏᴘᴛɪᴄᴀʟ ᴄᴇɴᴛʀᴇ ᴏғ ᴀ ʟᴇɴs, ɪs ᴄᴀʟʟᴇᴅ ɪᴛ's ғᴏᴄᴀʟ ʟᴇɴɢᴛʜ.