Physics — Geometric Optics

\frac{1}{f} = \frac{1}{v} - \frac{1}{u}

m = -\frac{v}{u} = \frac{h_i}{h_o}

n_1\sin\theta_1 = n_2\sin\theta_2

\sin\theta_c = \frac{n_2}{n_1}