As usual, you will be doing this lab experiment as a MATLAB live script. You will need to include a table of values this week. Please see this link from the Mathworks website: https://www.mathworks.com/matlabcentral/answers/492503-display-format-for-table-and-matrix-in-live-script for a good example. An easy way to determine the focal length of a converging lens is to form an image of a distant object that is hundreds, thousands, or more meters away. By the form of the thin lens equation, I imagine you can see how to determine the focal length once a well-focused image is formed. If it isn't clear, then just try some numbers - even if you don't know the precise object distance - and see what happens for an image distance of 20cm, for instance.

1. Set up each of the converging lenses (one at a time) on the optical bench (meter stick with clamps to hold lenses), along with a screen, and take the setup outside so that you can aim the lens toward a distant scene. 2. Change the separation distance between lens and screen until you get a focused image formed on the screen. 3. Measure the image distance for each lens... and make sure you will have a way of identifying each lens as you move forward with the lab. Q1: What was the measured image distance for each lens? Q2: What is the corresponding focal length measured this way (not the one listed on the packaging)? Q3: What is the percent error between the measured focal length and the lens specification on the packaging? Q4: What is the orientation of the image formed of the distant scene? Q5: Is it a real or virtual image?

1. Using the focal lengths from the last section, take each of the converging lenses and, one at a time, place them on the optical bench with object distances 2.0f, 1.5f, 1.0f, 0.7f, and record the corresponding image distances by moving the screen until a focused image is produced. If you cannot find a focused image, then look back through the lens to see if there is a virtual image on the same side as the light source. Record the focal length, along with image and object distances in a table for each case. 2. Calculate the percent difference between the experimental left side and right side of the thin lens equation above for each case. Put those values in the table.

The design of a refracting (lens-based) telescope is based on a housing to separate either two converging lenses, or one converging lens and one diverging lens. The two lenses are called the objective and the eyepiece. The eyepiece, as it sounds, is the one closer to your eye when using the telescope. In both designs, the magnitude of the focal length of the objective is larger. The ratio of those focal lengths is the magnification. Construct each type of telescope using your optical bench and answer the following questions about them: For the telescope with two converging lenses: 1. What is the orientation of the image that you see? 2. What is the expected magnification based on the focal lengths? 3. When focusing on a nearby, as compared to a distant object, do the lenses need to be closer together or farther apart to produce a focused image? For the telescope with one converging and one diverging lens: 4. Same as 1. 5. Same as 2. 6. Same as 3. 7. Which telescope do you suppose would be more useful for terrestrial imaging... like spotting land at sea or wildlife in nature?