Question

The power of a lens of focal length \[f = 0.5\,m\] is:

Options

• \[+0.5\,D\]

• \[+2\,D\]

• \[-2\,D\]

• \[+5\,D\]

Answer 1

Using \[P = \frac{1}{f}\] with \[f = 0.5\,m\]: \[P = \frac{1}{0.5} = +2\,D\]. The positive sign indicates a converging lens.