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| Light | The focal length of a telescope is the distance between the mirrot and the point where the light rays are focused by the mirror. The focal ratio is found by dividing the focal length by the diameter of teh mirror. For example, if a telescope has a focal length of 48 inches and a mirrot diameter of 6 inches, then the focal ratio is written f/8. a.)Find the foacl ratio of a telescope with a focal length of 154 inches and a mirror diameter of 14 inches. b.)The 200 inch Hale telescope on Mount Palomar in California is so large that the observer sits in a basket at the focal point inside the telescope. The focal ratio of the Hale telescope is f/3.3. How far from the mirror does the observer sit? Give your answer in inches, and then in feet.
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| Light | Suppose a mirrored surface has a cross section in the shape of one branch of a hyperbola. if a ray of light is headed toward the hyperbola's focus behind the mirror, the mirror will reflect the light through the other focus, as shown at the right. Draw a similar diagram for each of the following situations. a.)A mirrored surface has a cross section in the shape of a parabola. If a ray of light parallel to the parabola's axis of symmetry strikes the mirror, the mirror will f\reflect the light through the parabola's focus. b.)A mirrored surface has a cross section in the shape of one end of an ellipse. If a ray of light passes through the focus closest to the mirror and strikes the mirror, the mirror will reflect the light through the other focus.
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| Light | Can you give me info on how to make a periscope that can look over a 10ft wall out of pvc piping. Its for a public art project in australia. Referal to 'how to' books or web sites would be great. I've got the basic idea about two mirrors at 45 degrees - but I don't know how to get a decent view through pipe that long.
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| Light | I was given this problem, and did not know how to solve it: An object is placed 35 cm in frount of a covex mirror which has a Radius of curvature of 78 cm. If the object is 10cm high, where is the image formed, and how tall is it.
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| Light | Topic on Optics---Why does a stick partially appears bent? Wht is meant by the refractive index of a maedium?
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| Light | why is light bent by black holes if light does not have mass?
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| Light | Two light sources on a photometer bench are 90.0 cm apart. One light source is rated at 20.0 candela. The two sides of the photometer screen are equally illuminated when the screen is 40.0 cm from this source. What is the intensity of the other source?
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| Light | Suppose you are looking along the direction of propag
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| Light | We have a test for circular polarization. We have a li
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| Light | a submerged diver shines a light toward the surface of
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| Light | an air wedge is shown in fig 24.29. if the top glass pl
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| Light | A bird flies over a hill, its shadow falls onto the upw
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| Light | what is light ? how does light travel? light speed?
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| Light | in a lyods mirror interference expriment the source sli
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| Light | I would like to know how to figure out magnification of
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| Light | Can ordinary mass be converted into light and vivce-versa?
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