Question

The lateral magnification of a thin lens is m=-i/o. What is the longitudinal magnification, that is, the magnification in the direction of the optical axis?

Lots of explanation please :)

Answer 1

The longitude magnification in this case will be depicted as m^2 = (-i/o) ^2. This is because the longitudinal magnification of the lens and is the squared value of the lateral magnification. The thin lens equation is given by 1/s' = 1/s +1/f, where s is distance and f is focal length.

Also,

• Single lens: The linear magnification of a thin lens is

where is the focal length and is the distance from the lens to the object. Note that for real images, is negative and the image is inverted. For virtual images, is positive and the image is upright.

With being the distance from the lens to the image, the height of the image and the height of the object, the magnification can also be written as:

Note again that a negative magnification implies an inverted image.