Physics

Problem

A student wants a magnifying power of 10 with a simple magnifier when the final image is at infinity and his near point is

25\,\text{cm}

. The focal length of the lens he should choose is closest to a)

0.25\,\text{cm}

12.5\,\text{cm}

2.5\,\text{cm}

2.78\,\text{cm}