You decide to test your co workers idea with a

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You decide to test your co-worker's idea with a simplified optical system. You arrange a long filament bulb, lens and screen on an optical bench, so a focused image of the bulbs filament appears on the screen. Read Sternheim & Kane: sections 23.1, 23.4, 24.2 & 24.3 E QUIPMENT You have an optical bench, a convex lens mounted in a lens holder, a screen, long filament lamp, table clamp, three-finger clamp (to hold the lamp) and a ruler. If you need assistance, send an email to [email protected] . Include the room number and brief description of the problem. W ARM UP 1. Draw a fairly large sketch, showing a convex lens and a source of light that has a defined top and bottom. 2. Sketch the paths of two light rays from the top of the light source to the lens, and continue the sketch for each ray on the other side of the lens. (For the rays you choose, simple rules should tell you the path they take after passing through the lens, if confused, refer to your text.) Do you expect an image to form in this situation? If so, indicate the position of the image in your sketch. Where should you position the screen in order to see the image? 3. Repeat steps 1 and 2, placing the light source at one of the lens's focal points. Do you expect an image to form in this situation? 4. Repeat steps 1 and 2, placing the light source closer to the lens than its focal point. Do you expect an image to form in this situation? 5. What will happen to the image if the top half of the lens is covered? Indicate on your diagram which rays could pass through the lens in this situation, and which would be blocked. 12
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