Experiment 21-Geometric Optics Part 1-Parallax (set up) Draw one - PowerPoint PPT Presentation

Experiment 21-Geometric Optics

Part 1-Parallax (set up) Draw one line down the • middle of the long side of the paper Draw a line • perpendicular to the first line along the short side of the paper Place the mirror along • the short line Place a pin anywhere • along the normal in front of the mirror

Part 1-Parallax (perpendicular lines) Line up horizontal • line at bottom of protractor with already drawn line Perpendicular line • will be at 90 o

Part 1-Parallax (method) Notice the reflection of • the first pin in the mirror. THIS IS OBJECT 1 Place a second pin on the • normal behind the mirror. THIS IS OBJECT 2 Look to the left (or right) • of the closer pin At first the reflection and • the second pin you placed won’t line up Move object 2 so that it • lines up with object 1 (but keep object 2 along the normal)

Part 1-Parallax (method) Notice that the reflection • of the front pin (object 1) is lined up with the back pin (object 2) Good job  •

Part 2-Reflection (set up) Draw two • perpendicular lines and place mirror along the short line (like part 1) Use the protractor • to draw a line between 25 o -35 o Place two pins • along this line and label them P 1 and P 2

Part 2-Reflection (method) Move your head so that • the reflection of both pins in the mirror align with one another

Part 2-Reflection (method) Place down two pins so that they • line up with the reflections of P 1 and P 2 Label these pins P 3 and P 4 • Draw a line connecting P 3 and P 4 •

Part 2-Reflection (method) Top down view of final result •

Part 3-Refraction (set up) Place square plexiglass • in center of page Trace its outline •

Part 3-Refraction (set up) Draw a normal line from the top • left corner of the outline (2 cm) Use the protractor to draw a line • between 25 o -35 o from the normal (like in part 3) Place two pins along this line and • label them P 1 and P 2

Part 3-Refraction (method) Place the square lens on • top of its outline Look through the bottom • of the lens to find the image of P 1 and P 2 * * You can place a blank sheet of paper behind the lens to make this easier for you

Part 3-Refraction (method) Move your head so • that the images of the two pins line up with one another

Part 3-Refraction (method) Place two pins down so • that they line up with the images of P 1 and P 2 Label these new pins P 3 • and P 4

Part 4-Total Internal Reflection (set up) Place triangle plexiglass • lens on paper and trace its outline

Part 4-Total Internal Reflection (set up) Draw a line perpendicular to • the left vertex of the long side on the lens (like in part 4) 1 cm from the vertex Place two pins along this • line and label them P 1 and P 2

Part 4-Total Internal Reflection (method) Look through the bottom of • the lens and line up the images of P 1 and P 2 (like in part 4)* *You can place a blank sheet of paper behind the lens to make this easier for you

Part 4-Total Internal Reflection (method) Place down two pins so that • they align with the images of P 1 and P 2 (like part 4) Label these two pins P 3 and P 4 •

Part 4-Total Internal Reflection (method) Draw a line connecting P 3 and • P 4 with the base of the lens outline Extend these lines through the • lens outline to the far side of the triangle Draw a line across the triangle • connecting the extensions of P 1 P 2 and P 3 P 4 Top down view of the final • result