Question Detail
Question
When calculating the power of a lens using the formula Power = 1/focal length, what unit must the focal length be expressed in?
Correct Answer
Option C is the correct answer.
Detailed Explanation
The document specifies: 'Note that the units of focal length must be in meters when using this expression.' This is crucial for obtaining power in diopters.
Hint
The unit of power is diopters, and it requires a specific unit for focal length.