Lens Image Distance Example

Lens Image Distance Example
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2014-07-29 04:21
In collections CCGPS AA Unit 6 Lesson 5
This example demonstrates the relationship between object distance (d₁) and image distance (d₂) in lens imaging, highlighting geometric mean properties. Core concepts include object/image distances, geometric mean, and lens imaging formulas. GeoGebra commands like LaTeX, points, circumcircle arcs, vectors, and midpoints are used in construction. Suitable for high school physics and mathematics education on optics and geometric modeling.

GeoGebra Commands & Parameters

  1. LaTeX(steps) → counter
  2. LaTeX("\text{Move the slider to solve the problem.}") → text0
  3. Corner(1) → A
  4. Corner(3) → B
  5. Point(xAxis) → D
  6. CircumcircleArc(C, D, F_1) → c
  7. CircumcircleArc(I, J, H) → d
  8. CircumcircleArc(G, D, E) → e
  9. CircumcircleArc(E, J, G) → f
  10. Segment(C, H) → b
  11. Segment(F_1, I) → g
  12. If(sgn(focal) < 0, "f<0", "f>0") → focaltext
  13. Vector((0, -1.25), (x(F), (-1.25))) → u
  14. Midpoint((0, -1.25), (sgn(focal), (-1.25))) → M
  15. LaTeX("d_{image}<0") → imagetextneg
  16. Vector((0, -1.77), (-1.5, -1.77)) → v
  17. Midpoint((0, -1.77), (-1.5, -1.77)) → N
  18. Vector((0, -1.73), (1.5, -1.73)) → w
  19. Midpoint((0, -1.73), (1.5, -1.73)) → O
  20. LaTeX("d_{image}>0") → imagetextpos
  21. Vector((0, 1.23), (-1.5, 1.23)) → h
  22. Midpoint((0, 1.23), (-1.5, 1.23)) → P
  23. Vector((0, 1.27), (1.5, 1.27)) → i
  24. Midpoint((0, 1.27), (1.5, 1.27)) → Q
  25. LaTeX("d_{object}>0") → objecttextpos
  26. LaTeX("d_{object}<0") → objtextneg
  27. Line((-1, 0), (1, 0)) → j
  28. Line((0, -1), (0, 1)) → k
  29. LaTeX("\textcolor{#000099}{f=\frac{d_{object}d_{image}}{d_{object}+d_{image}}}") → text3
  30. If(focal < 0, LaTeX[("-d_{object}+" * diff)], LaTeX[("d_{object}+" * diff)]) → drelation
  31. LaTeX((((("\textcolor{#000099}{f=" * focal) * "}\cr\textcolor{#000099}{d_{image}= ") * drelation) * "}")) → Problem
  32. If(focal < 0, LaTeX[diff], LaTeX[("2d_{object}+" * diff)]) → denominator
  33. If(focal < 0, LaTeX[(("-d_{object}^2+" * diff) * "d_{object}")], LaTeX[(("d_{object}^2+" * diff) * "d_{object}")]) → numerator
  34. LaTeX((("\text{Multiply both sides by }\textcolor{#000099}{" * denominator) * "}.")) → text8
  35. If(focal < 0, LaTeX[(focal * diff)], LaTeX[(((focal * 2) * "d_{object}+") * focaldiff)]) → leftside
  36. LaTeX((((((("\textcolor{#000099}{" * focal) * "=\frac{") * numerator) * "}{") * denominator) * "}}")) → text7
  37. LaTeX((((("\textcolor{#000099}{" * leftside) * "=") * numerator) * "}")) → text9
  38. If(focal < 0, LaTeX[(("\text{Subtract }\textcolor{#000099}{" * numerator) * "}\text{ from both sides.}")], LaTeX[(("\text{Subtract }\textcolor{#000099}{" * leftside) * "}\text{ from both sides.}")]) → text10
  39. If(focal < 0, LaTeX[(((("\textcolor{#000099}{d_{object}^2-" * diff) * "d_{object}") * leftside) * "=0}")], LaTeX[(((("\textcolor{#000099}{d_{object}^2 +(" * linterm) * ")d_{object}-") * focaldiff) * "=0}")]) → text11
  40. LaTeX("\text{}") → text14
  41. If(focal < 0, Polynomial[x^(2) - (diff * x) + (focal * diff)], Polynomial[x^(2) + ((diff - (2 * focal)) * x) - (focal * diff)]) → p
  42. Unique(Zip[x(a), a, zeropts]) → zeros
  43. Length(zeros) → numzeros
  44. If(Element[zeros, Length[zeros]] ≟ 0 ∨ Element[zeros, 1] ≟ 0, LaTeX["\text{A zero value for }\textcolor{#000099}{d_{object}}\text{ makes no}\cr\text{sense because the object will be in the}\cr\text{middle of the lens.}"], "") → zeroroot
  45. If(Element[zeros, 1] < 0, LaTeX["\text{A negative value for }\textcolor{#000099}{d_{object}}\text{ means the object is on}\cr\text{the right side of the lens. This is a virtual object}\cr\text{which typically occurs only in multi-lens systems.}\cr"], "") → negroot
  46. If(Element[zeros, Length[zeros]] > 0, LaTeX["\text{A positive value for }\textcolor{#000099}{d_{object}}\text{ means the object is on}\cr\text{the left side of the lens.}\cr"], "") → posroot
  47. LaTeX(((negroot * posroot) * zeroroot)) → text17
  48. LaTeX("\textcolor{#000099}{x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}}") → text20
  49. If(focal < 0, (focal * diff), ((-focal) * diff)) → quadc
  50. If(focal < 0, (-diff), diff - (2 * focal)) → quadb
  51. LaTeX((((((("\textcolor{#000099}{d_{object}=\frac{-(" * quadb) * ")\pm\sqrt{(") * quadb) * ")^2-4(1)(") * quadc) * ")}}{2(1)}}")) → text22
  52. LaTeX("\text{Simplify.}") → text23
  53. LaTeX((("\textcolor{#000099}{d_{object}=" * zeros) * "}")) → text24
  54. If(focal > 0, Zip[a + diff, a, zeros], Zip[(-a) + diff, a, zeros]) → images
  55. LaTeX("\text{Find }\textcolor{#000099}{d_{image}}\text{ and interpret the result in terms of the}\cr\text{image location relative to the lens.}") → text25
  56. LaTeX((("\textcolor{#000099}{d_{image}=" * images) * "}")) → text26
  57. If(Min[images] < 0, LaTeX["\text{A negative value for }\textcolor{#000099}{d_{image}}\text{ means the image is on}\cr\text{the left side of the lens.}\cr"], "") → negimage
  58. If(Max[images] > 0, LaTeX["\text{A positive value for }\textcolor{#000099}{d_{image}}\text{ means the image is on}\cr\text{the right side of the lens.}\cr"], "") → posimage
  59. If(Element[images, Length[images]] ≟ 0 ∨ Element[images, 1] ≟ 0, LaTeX["\text{A zero value for }\textcolor{#000099}{d_{image}}\text{ makes no sense because}\cr\text{the image will be in the middle of the lens.}"], "") → zeroimage
  60. LaTeX(((negimage * posimage) * zeroimage)) → text27
  61. Vector(((-Element[zeros, chooseSolution]), 0), ((-Element[zeros, chooseSolution]), 1)) → l
  62. Vector((Element[images, chooseSolution], 0), (Element[images, chooseSolution], ((-Element[images, chooseSolution])) / Element[zeros, chooseSolution])) → m
  63. LaTeX((((("\textcolor{#000099}{d_{object}=" * Element[zeros, chooseSolution]) * "}\cr \textcolor{#006633}{d_{image}=") * Element[images, chooseSolution]) * "}")) → text28
  64. Vector((((-1.5) * abs(focal)), 0.5), (((-0.5) * abs(focal)), 0.5)) → n
  65. Vector((((-1.5) * abs(focal)), (-0.5)), (((-0.5) * abs(focal)), (-0.5))) → q
  66. LaTeX("\text{Use the buttons below to return to the original problem or}\cr\text{randomly generate a similar practice problem.}") → RandomizationText
  67. LaTeX("\text{Substitute the defined variables into the thin lens equation and simplify.}") → text1
  68. LaTeX("\text{Given function}") → text2
  69. LaTeX((((((("\textcolor{#000099}{(" * focal) * ")=\frac{d_{object}(") * drelation) * ")}{d_{object}+(") * drelation) * ")}}")) → text5
  70. If(focal < 0, LaTeX[(((("\text{Graph the simplified equation }\cr\textcolor{#000099}{d_{object}^2-" * diff) * "d_{object}") * leftside) * "=0}.")], LaTeX[(((("\text{Graph the simplified equation }\textcolor{#000099}{d_{object}^2 +(" * linterm) * ")d_{object}-") * focaldiff) * "=0}.")]) → text13
  71. LaTeX("\text{Describe the zeros of the function and what that implies for the number of }\cr\text{possible solutions for }\textcolor{#000099}{d_{object}}\text{ and }\textcolor{#000099}{d_{image}.}") → text15
  72. LaTeX((((((("\text{There are " * numzeros) * " possible positions for the object so that}\cr\textcolor{#000099}{d_{image}=") * drelation) * "}\text{ is true for a focal length of }\textcolor{#000099}{f=") * focal) * "}.")) → text16
  73. LaTeX("\text{Quadratic formula}") → text19
  74. LaTeX((((("\text{Substitute }\textcolor{#000099}{d_{object}}\text{ for }\textcolor{#000099}{x}\text{, }\cr\textcolor{#000099}{1}\text{ for }\textcolor{#000099}{a}\text{, }\textcolor{#000099}{" * quadb) * "}\text{ for }\textcolor{#000099}{b}\text{,}\cr\text{and }\textcolor{#000099}{") * quadc) * "}\text{ for }\textcolor{#000099}{c}.")) → text21
  75. LaTeX("\text{Solve the simplified formula for }\textcolor{#000099}{d_{object}.}") → text18
  76. LaTeX((((("\text{Substitute the given focal length, }\textcolor{#000099}{f=" * focal) * "}\text{,}\cr\text{and the relationship between the image and}\cr\text{object distances, }\textcolor{#000099}{d_{image}=") * drelation) * "}.")) → text4
  77. LaTeX("\text{Simplify the numerator and denominator.}") → text6
  78. If(focal < 0, LaTeX[(((("\text{The simplified function can be written as }\cr\textcolor{#000099}{d_{object}^2-" * diff) * "d_{object}") * leftside) * "=0}\text{.}")], LaTeX[(((("\text{The simplified function can be written as }\cr\textcolor{#000099}{d_{object}^2 +(" * linterm) * ")d_{object}-") * focaldiff) * "=0}\text{.}")]) → text12
  79. LaTeX("\text{Move the slider to change the object's location.}") → text29

AI Drawing Prompt Reference

Draw a geometric model of lens imaging to show the relationship between object distance and image distance, using arcs to represent light paths and highlighting geometric mean properties. Include coordinate axes, focal points, object and image points, vectors for light paths, different colors for positive and negative values, and the formula derivation process to finally obtain the mathematical relationship between object and image distances.
The prompt above was compiled from the original drawing commands and is for reference only.