a convex lens forms a real and inverted image of needle at a distance of 50cm from it Where - Physics - Refraction of light

Question

a convex lens forms a real and inverted image of needle at a
distance of 50cm from it Where is the needle placed in front of
convex lens if the image is equal to the size of object? also find
the power of lens

Abhishek Gupta · Accepted Answer

Dear Student!
A convex lens forms a real and inverted image of equal size
only when it is kept at the center of curvature of the lens The
image is also formed at the center of curvature at the other
side
Hence, the distance of object = distance of image = 50
cm
Now, focal length = ½ × radius of curvature =
½ × 50 cm = 25 cm
Hope it is clear!
Best wishes!!

a convex lens forms a real and inverted image of needle at a distance of 50cm from it. Where is the needle placed in front of convex lens if the image is equal to the size of object? also find the power of lens