Physic Labs

Problem 3

An object is placed a distance u>fu>f from a converging thin lens of focal length ff. Find the image distance vv and transverse magnification mm, and state whether the image is real or virtual. (a) State the assumptions and establish the governing equation for the requested quantity. (b) Solve it in terms of the given symbols, identifying the direction, sign, or physical nature of the result. (c) Check a simple limiting case and state when the model remains valid. Use SI units consistently, retain the symbols in the setup, and enforce all geometric constraints and initial conditions.
v=fuu−fv=\frac{fu}{u-f}
problems.proof.analysis

Taking the reciprocal gives the image distance; the positive sign places the image on the opposite side of the lens.