Question

For a convex lens, the minimum distance between an object and its real image in terms of focal length (f) of a given lens must be:

(a) 1.5 f
(b) 2.5 f
(c) 2 f
(d) 4 f

Answer 1

The minimum distance between an object and its real image for a convex lens is 4 times the focal length of the lens, since the closest the object and image distances are when both are at 2f, leading to a total minimum distance of 4f.

Step-by-step explanation:

The minimum distance between an object and its real image for a convex lens in terms of the focal length (f) of the lens can be found using the lens equation 1/f = 1/do + 1/di, where do is the object distance and di is the image distance from the lens. For a real image, both the object and the image have to be on the opposite sides of the lens. The closest the object and image can be to each other and still form a real image is when they are both at 2f, as this is the position in which the image is at the same distance as the object from the lens and they are equally spaced around the focal point.

The correct answer to the question about the minimum distance between an object and its real image in terms of the focal length of a convex lens is (c) 4f, as both the object distance and image distance contribute 2f each, making the total minimum distance 4f.

Answer 2

The minimum distance between an object and its real image for a convex lens is 4 times the focal length of the lens, since the closest the object and image distances are when both are at 2f, leading to a total minimum distance of 4f.

Step-by-step explanation:

The minimum distance between an object and its real image for a convex lens in terms of the focal length (f) of the lens can be found using the lens equation 1/f = 1/do + 1/di, where do is the object distance and di is the image distance from the lens. For a real image, both the object and the image have to be on the opposite sides of the lens. The closest the object and image can be to each other and still form a real image is when they are both at 2f, as this is the position in which the image is at the same distance as the object from the lens and they are equally spaced around the focal point.

The correct answer to the question about the minimum distance between an object and its real image in terms of the focal length of a convex lens is (c) 4f, as both the object distance and image distance contribute 2f each, making the total minimum distance 4f.

Answer 3

The minimum distance between an object and its real image for a convex lens is 4 times the focal length of the lens, since the closest the object and image distances are when both are at 2f, leading to a total minimum distance of 4f.

Step-by-step explanation:

The minimum distance between an object and its real image for a convex lens in terms of the focal length (f) of the lens can be found using the lens equation 1/f = 1/do + 1/di, where do is the object distance and di is the image distance from the lens. For a real image, both the object and the image have to be on the opposite sides of the lens. The closest the object and image can be to each other and still form a real image is when they are both at 2f, as this is the position in which the image is at the same distance as the object from the lens and they are equally spaced around the focal point.

The correct answer to the question about the minimum distance between an object and its real image in terms of the focal length of a convex lens is (c) 4f, as both the object distance and image distance contribute 2f each, making the total minimum distance 4f.