A convex lens produces a real image m times the size of the object. What will be the distance of the object from the lens?

Question

A convex lens produces a real image m times the size of the object. What will be the distance of the object from the lens? (A) ((m+1/m)) f (B) (m-1) f (C) ((m-1/m)) f (D) (m+1/f)

Tardigrade Admin · Accepted Answer

m=(f/f+u) ⇒ -m=(f/f+u) ⇒ u=-((m+1/m)) f

Q. A convex lens produces a real image $m$ times the size of the object. What will be the distance of the object from the lens?

$(\frac{m + 1}{m}) f$

$(m - 1) f$

$(\frac{m - 1}{m}) f$

$\frac{m + 1}{f}$

$m = \frac{f}{f + u} \Rightarrow - m = \frac{f}{f + u}$
$\Rightarrow u = - (\frac{m + 1}{m}) f$

Q. A convex lens produces a real image m times the size of the object. What will be the distance of the object from the lens?

(mm+1​)f

(m−1)f

(mm−1​)f

fm+1​