Question

An arrow and a lens are shown. The distance between the arrow and the lens equals twice the focal length, f, of the lens. Which number is closest to the location of the arrow tip of the image produced by the lens?

Answer 1

The image is located at number 4

Step-by-step explanation:

As we know that object is located at the position

`d_o = 2f`

now for the position of image we can use lens formula as

`(1)/(d_i) + (1)/(d_o) = (1)/(f)`

now we have

`(1)/(d_i) + (1)/(2f) = (1)/(f)`

now we have

`d_i = 2f`

also we know that the magnification is given as

`m = (d_i)/(d_o)`

`m = (2f)/(-2f) = -1`

so image will be inverted and its position is 2f

so correct number will be 4