Question

1. What is the image distance and image size if a 10.00 cm. tall light bulb placed a distance of 91 cm. from a convex lens having a focal length of 30.8 cm ?

Answer 1

By the convex mirror equation:

$$\frac1f=\frac1o+\frac1i,\\\space\\ i=\frac{fo}{o-f}=46.6\text{ cm},\\\space\\ h_i=-\frac{i}{o}h_o=5.12\text{ cm}.$$