Show algebraically, that an object placed a little less than 1 focal length away from a...

Question

Question

Show algebraically, that an object placed a little less than 1 focal length away from a lens forms a virtual image far away.

Answer 1

Answer #1

using lens formula

1/f = 1/ v + 1/ u

1/ f - 1/ u = 1/v

(u - f) / uf = 1/v

v = uf / ( u - f)

now as u < f, so factor ( u - f) will be negative,

hence v is negative and negative image distance leads to virtual image.

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Comment in case any doubt, will reply for sure . Goodluck

Answer 2

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