At what distance from a biconvex lens of the focal length F, must be placed an object for the distance between the object and its real image to be minimal?

Question

At what distance from a biconvex lens of the focal length F, must be placed an object for the distance between the object and its real image to be minimal? (A) 2F (B) F (C) (F/2) (D) 4 F

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/71dd590ed8febcb3e17ac181465916a1-.png" /> Minimum distance of an object and its real image is 4 F. For this, object must be placed at distance 2 F from lens.

Q. At what distance from a biconvex lens of the focal length $F$ , must be placed an object for the distance between the object and its real image to be minimal?

$2 F$

$F$

$\frac{F}{2}$

$4 F$

Minimum distance of an object and its real image is $4 F$ . For this, object must be placed at distance $2 F$ from lens.

Q. At what distance from a biconvex lens of the focal length F, must be placed an object for the distance between the object and its real image to be minimal?

2F

F

2F​

4F

Minimum distance of an object and its real image is 4F. For this, object must be placed at distance 2F from lens.

Q. At what distance from a biconvex lens of the focal length $F$ , must be placed an object for the distance between the object and its real image to be minimal?

$2 F$

$F$

$\frac{F}{2}$

$4 F$

Minimum distance of an object and its real image is $4 F$ . For this, object must be placed at distance $2 F$ from lens.