A lens has a power of +2 diopters. What is its focal length?
Practice Questions
Q1
A lens has a power of +2 diopters. What is its focal length?
0.5 m
1 m
2 m
3 m
Questions & Step-by-Step Solutions
A lens has a power of +2 diopters. What is its focal length?
Step 1: Understand that the power of a lens (P) is measured in diopters (D). In this case, the power is +2 diopters.
Step 2: Recall the formula that relates power (P) to focal length (f): P = 1/f, where f is in meters.
Step 3: Rearrange the formula to find the focal length: f = 1/P.
Step 4: Substitute the value of power into the formula: f = 1/2.
Step 5: Calculate the focal length: f = 0.5 meters.
Lens Power and Focal Length – The relationship between the power of a lens and its focal length, where power is the reciprocal of the focal length in meters.