What is the power of a lens with a focal length of 2 meters?

The power of a lens is calculated using the formula:

[ \text{Power} (P) = \frac{1}{\text{Focal Length} (f)} ]

where the focal length is measured in meters and power is measured in diopters (D).

In this case, the focal length of the lens is 2 meters. Plugging this value into the formula gives:

[ P = \frac{1}{2 \text{ m}} = 0.5 \text{ D} ]

This calculation shows that the lens has a power of 0.50 diopters. Therefore, the correct answer aligns with the formula and its application to the given focal length, confirming that the power of the lens is indeed 0.50 D. The calculations based on the focal length provide a straightforward method for determining lens power in optics.