1. Three rays can be used to determine the location of images produced by thin lenses.  This process is called Geometric Optics.  The first rule is that a ray parallel to the principle axis is refracted through the far focal point.  The second is that a ray through the near focal point is refracted parallel to the principle axis.  The third is that a ray through the optical center is not refracted but keeps moving is a straight line.
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3. Important Formulas:    
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5. Procedure:
6.               Converging Lens
7.  Go to https://ket.pbslearningmedia.org/resource/arct15-sci-lensmirrorlab/lens-and-mirror-lab/ to open the simulation. 
8. Click on the image to launch the simulation.
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10. From the upper left corner choose the arrow as your image and make sure the Converging option is selected.
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12. Adjust the focal length to be 20 cm and the Object height to be 10. 
13. Click and hold down on the image arrow (on the left) and drag it to an Object Distance of 50.0 cm. 
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15. Record the image distance and image height in data table I.
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17. Calculate the image distance and image height for each trial.  Be sure to show your calculations for trial 1 in the spaces provided on the Submission Form.
18. Repeat the experiment and calculations for object distances of 30 cm and 10 cm.
19. For each object distance determine if the image is virtual or real.       Put your answers in Table II.      Explain your answer for all three trials in the area provided.
20. For each object distance determine if the image is upside down or right side up.  Explain your answers in the area provided.
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22. Diverging Lens
23. From the top orange bar, now choose Diverging.
24. Repeat the experiment for the objct distances of 50, 30, and 10 cm and record your results in Data Table III.  Be careful with your calculations.   Remember the focal length of a diverging lens is negative.
25. Complete Table IV for the correct type of image and orientation.
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27. Conclusion Questions - Answer the questions found on the Submission Form.  You may need to leave the simulation open to answer some of the questions.
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29. Geometric Optics Assignment
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31. Converging Lens
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33. Data Table I: Converging Lens (20 Points)

Object Height	Object Location	Measured Image Distance	Measured Image Height	Calculated Image Distance	Calculated Image Height
10.0 cm	50.0 cm
10.0 cm	30.0 cm
10.0 cm	10.0 cm

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2. Sample Calculation of Image Distance (5 Points)
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6. Sample Calculation of Image Height (5 Points)
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10. Table II (10 Points)

Object Height	Object Location	Real/Virtual	Upside Down/Right Side Up
10.0 cm	50.0 cm
10.0 cm	30.0 cm
10.0 cm	10.0 cm

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2. Explain your choice of Real or Virtual for each trial. (5 Points)
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8. Explain your choice of Upside Down or Right Side Up for each trial. (5 Points)
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14. Diverging Lens
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16. Data Table III: Diverging Lens (16 Points)

Object Height	Object Location	Measured Image Distance	Measured Image Height	Calculated Image Distance	Calculated Image Height
10.0 cm	60.0 cm
10.0 cm	40.0 cm
10.0 cm	20.0 cm

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3. Table IV (9 Points)

Object Height	Object Location	Real/Virtual	Upside Down/Right Side Up
10.0 cm	60.0 cm
10.0 cm	40.0 cm
10.0 cm	20.0 cm

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2. Conclusion Questions: (You may need to leave the simulation open to answer some of the questions.) (5 Points Each)
3.  What is the general pattern of image distance as the object is moved from a large distance toward the focal point?
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5. How would this translate to the magnification of the image? Explain.
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7. What is the general pattern of the image distance as the object is moved inside the focal point and brought closer to the lens?
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9. How would this translate to the magnification of the image?
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11. What is the general pattern of the image distance and magnification as the focal length became smaller?
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