Calculate lens focal length, refractive index, and wavelength properties
Lens Formula
1/f = 1/v – 1/u
cm
cm
Focal Length
20.00 cm
Note: Object distance (u) is typically negative for real objects. Positive image distance (v) indicates a real image.
Refractive Index
n = c / v
m/s
m/s
Refractive Index
1.50
Reference: Water ≈ 1.33, Glass ≈ 1.5, Diamond ≈ 2.42
Wavelength
λ = c / f
m/s
Hz
Wavelength
600 nm
Visible Light: 380-700 nm. Example shows orange light at ~600 nm.
Understanding Optics
Lens Formula: Relates the object distance (u), image distance (v), and focal length (f) of a lens. By convention, distances are measured from the optical center of the lens, with real objects having negative u values.
Refractive Index: Measures how much light slows down when entering a medium. A higher refractive index means light travels slower in that medium, causing more bending at the interface.
Wavelength: The distance between successive crests of a wave. Related to frequency and speed by λ = c/f. Different wavelengths of visible light correspond to different colors.
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