We've evolved over millions of years to sense the world around us. When we encounter something, someone or some place, we use our five natural senses to perceive information about it; that information helps us make decisions and chose the right actions to take.
Two converging achromatic lenses with focal lengths of about 6 cm and 13 cm Graphical Analysis software Vertical rod in table-top stand Printed arrow Font size 11 Smart phone with camera or webcam Support ring for Phone Physical Principles: Focal Length For the rays shown in Figureslight is assumed to be coming from the left, and going toward the right.
A converging lens always has two focal points, the primary focal point on the near side of the lens towards the oncoming light rays and a secondary focal point on the far side of the lens away from the oncoming light rays.
Light diverging from the primary focal point and approaching a converging lens will exit the lens with the rays parallel. Parallel light rays approaching a converging lens will converge at the secondary focal point. See Figures 1 and 2.
Light coming from very distant objects can be approximated with parallel rays. The distance from the lens to the focal points is called the focal length. For a converging lens, the focal length is always positive, for a diverging lens it is always negative.
Ray Diagrams A Ray Diagram is a graphical method of predicting the characteristics of an image produced by a lens. First draw a set of axis and draw the lens at the origin. Then locate the position of the two focal points and the object.
This should be done to scale so that the position and size of the resulting image are accurate. Next draw the three reference rays: Reference rays originate from the object, travel through the lens and are refracted.
Where any two rays intersect, the image is formed. The third ray should pass through the same intersection point; this just confirms the location of the image.
Remember, light is refracted differently when encountering converging and diverging lens, the rays will be refracted in different ways. Ray Diagram for a converging lens.
The Parallel Ray 1 is drawn parallel to the axis then refracted towards the back focal point. The Central Ray 2 proceeds straight through he center of the lens.
The Focal Ray 3 is drawn towards the focal point then refracted parallel to the axis. The image is formed where the three rays meet. Put a 13 cm converging lens in a lens holder and put the holder rod in an optical bench carriage. Place a white screen into a screen holder with the white surface against the clamping screw, the screen surface is then centered above the rod.
Put the screen holder rod into a carraige and place it on the optical bench. Align the lens and screen perpendicular to the optical bench.
Use a light source across the room or out the windowas far away as possible - at least 50 times the focal length, and direct the light from this source through the 13 cm converging lens onto the projection screen.
Adjust the position of the screen for sharp focus. Record the position of the lens, xL, and screen, xS, on the optical bench and estimate the focal length as the difference xS - xL.
Converging Lens Setup Place an object slide together with an aperture into a screen holder and insert the holder rod into a carriage. Place the carriage on the optical bench and position it so that the fiducial mark is as near 0 cm as possible. Record this position as x0.
Do not change this position during this part of the experiment. Place the carriage with the small 13 cm achromatic lens on the optical bench at about 50 cm or the middle of the bench.
Place the carriage with the screen at the cm position. Adjust the heights of the centers of the lens, object, aperture and screen so their heights are the same and align them perpendicular to the optical bench.
Move the lens away from the screen until a sharp image is observed.The Purdue Writing Lab Purdue University students, faculty, and staff at our West Lafayette, IN campus may access this area for information on the award-winning Purdue Writing Lab.
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SixthSense is a wearable gestural interface that augments the physical world around us with digital information and lets us use natural hand gestures to interact with that information. Pranav Mistry of MIT Media Lab is the inventor of the SixthSense.
A&P 1 INTERNET DOWNLOAD LAB REPORT Name _____ Lab # 1 Lab Title MICROSCOPY Date _____ What Do I Need To Hand In For This Lab? Beaker #1 was the most significant change with a percent difference of making it almost half of the potatoes mass.
From the data obtained we can concur that the most likely result of the loss of mass is due to the water leaving the potato.
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