To find the focal length of a lens given its power, we can use the formula:
[tex]\[ f = \frac{1}{P} \][/tex]
where:
- [tex]\( f \)[/tex] is the focal length in meters,
- [tex]\( P \)[/tex] is the power of the lens in diopters (D).
Given that the power of the lens [tex]\( P \)[/tex] is [tex]\( -2 \)[/tex] diopters, we can substitute [tex]\( P \)[/tex] into the formula:
[tex]\[ f = \frac{1}{-2} \][/tex]
This simplifies to:
[tex]\[ f = -0.5 \][/tex]
Therefore, the focal length of the lens is [tex]\( -0.5 \)[/tex] meters.
Thus, the correct option is:
d) [tex]\(-0.5 \, \text{m}\)[/tex]
