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Thin lens equation relates object distance, image distance, and focal length. It's fundamental to cameras, microscopes, telescopes, and corrective lenses.
Formel
The calculator applies 1/f = 1/s_o + 1/s_i
- f
- 1/s_o + 1/s_i — 1/s_o + 1/s_i
Trin-for-trin guide
- 1Enter any two of: object distance (s_o), image distance (s_i), or focal length (f)
- 2The calculator applies 1/f = 1/s_o + 1/s_i
- 3Results show lens behavior and image characteristics
Løste eksempler
Input
s_o = 30 cm, f = 10 cm
Resultat
s_i = 15 cm, magnification = 0.5×
Real inverted image
Almindelige fejl at undgå
- ✕Confusing sign conventions for distances and focal lengths
- ✕Using lens equations without considering real vs. virtual images
Ofte stillede spørgsmål
When do you get virtual images?
Virtual images form when the object is closer than the focal point (s_o < f); the image appears upright and magnified.
What's the difference between converging and diverging lenses?
Converging (convex) lenses have positive focal length and form real images; diverging (concave) lenses have negative focal length and only form virtual images.
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