physics, lenses
posted by Anonymous .
I need to calculate the magnification, m of an objective lens, so I can then x it by the eyepiece value for M to get the total magnification.
I need v/u (v is dist from lens to image; u is dist of object to lens)
I'm using 1/f = 1/v+1/u rearranged for 1/v.
That's: 1/v = 1/f  1/u. I think?
The object is 26mm away from the lens; the focal length is 25mm.
I keep getting v = 500mm! (650mm too).
Any ideas where i'm going wrong please?
Thanks.

it depends on the position of the object. u need to c that if v and u bth are on same side or opposite side because that changes the sign of v and u to positiv and negative. i hope u gt tht