An object is placed 40 cm from a convex lens of focal length 20 cm. Calculate image distance.

v = 10 cm

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v = 20 cm

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v = 40 cm

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v = 60 cm

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Solution

The correct option is C v = 40 cm
Given,
Object distance (u) = 40 cm
Focal length (f) = 20 cm
So,
Using lens formula
$\frac{1}{v} - \frac{1}{u} = \frac{1}{f}$

$\frac{1}{v} - \frac{1}{- 40} = \frac{1}{20}$

v = 40 cm

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An object is placed 40 cm from a convex lens of focal length 20 cm. Calculate image distance.

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(a) An object is placed at a distance of more than 40 cm from a convex lens of focal length 20 cm. The image formed is real, inverted and ..........

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For an object placed at a distance 20 cm in front of a convex lens, the image is at a distance 20 cm behind the lens. The focal length of convex lens is :

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Q. The size of the image of an object, which is at infinity, as formed by a convex lens of focal length

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An object is placed 40 cm from a convex lens of focal length 20 cm. Calculate image distance.

The correct option is C v = 40 cmGiven, Object distance (u) = 40 cm Focal length (f) = 20 cm So, Using lens formula 1v−1u=1f 1v−1−40=120 v = 40 cm

The correct option is C v = 40 cm
Given,
Object distance (u) = 40 cm
Focal length (f) = 20 cm
So,
Using lens formula
$\frac{1}{v} - \frac{1}{u} = \frac{1}{f}$

$\frac{1}{v} - \frac{1}{- 40} = \frac{1}{20}$

v = 40 cm