When the distance between the object and the screen is more than `4 f`. We can obtain image of the object on the screen for the two positions of the lens. If is called displacement method. In one case, the image is magnified and in the other case, it is diminished. If `I_(1)` and `I_(2)` be the sized of the two images, then the size of the object is

Options

A. `sqrt(I_(1)I_(2))`
B. `sqrt((I_(1))/(I_(2)))`
C. `I_(1)-I_(2)`
D. `(I_(1)+I_(2))/(2)`

Answer

A

Explanation

`(I_(1))/(O)=(v)/(u),=(u)/(v),(I_(1)I_(2))/(O_(2))=I,O=sqrt(I_(1)I_(2))`