At wat distance from the primary mirror should i put the diagonal in a newtonian telescope.?
474015
As the focal length was not mentioned it's impossible to measure the distance between primary mirror and diagonal. I calculated that it should be more than a meter if the f ratio is high enough.\nI don't need be an Indian to see Indian movies. DVDs are released worldwide. However, I am neither from S.P.A.C.E nor from Galileo. I run an astronomy organization myself. I'm associated with many other international organizations.
590082
1) Let's think about this problem two-dimensionally.  A cross-section of the parabolic mirror would simply be a parabola.  Let's translate this onto a Cartesian coordinate system with (0,0) as the center.  Then (0,35) would be the focus, y=-35 would be the directrix, and one of the upper points would be (27,y).  If we find y, we find the depth of the mirror.  Since the points on a parabola are those points that are equidistant from the focus and directrix, let's set these distances equal to one another.  The distance between the focus--(0,35)--and the top point--(27,y)--is given by sqrt((35-y)^2 + 27^2).  The (shortest) distance between the directrix--y=-35--and the top point--(27,y)--is simply y+35.  Setting these two distance equal, we solve for y:\n\nsqrt((35-y)^2 + 27^2) = y+35\n(35-y)^2 +729 = (y=35)^2     (square both sides)\n1225 - 70y + y^2 + 729 = y^2 + 70y + 1225       (simplify)\n729 = 140y    (simplify)\ny = 729/140\n\nThus, the depth of the mirror is 729/140 ft.\n\n\n\n2) We must assume this 6% is an annual interest rate.  Then, the problem is simple.  A = P * (1 + r/n)^(nt), where A is the ending amount, P is the principal, r is the annual percentage rate as a decimal or fraction, n is the number of times compounded per year, and t is the number of years.\n\nIn this example, P = 6000, r = 0.06, n = 4, and t = 10.  Plugging these numbers into the above formula, we find that A = 10884.11.\n\nThus, after ten years, there is $10884.11 in the account.\n\nGood luck!
583825
take above as :-\nm= -v/u = h'/h = 2h/h = 2\n-v/u = 2, v = -2u\ntake,\n1/f = 1/v + 1/u\n1/-50cm = 1/-2u + 1/u\n(-50) because focal length of concave mirror is always negative.\n\n\nnow, solve it get value of 'u'& you will get ur object distance.\nit must be less than 0.5 m as the image is erect & enlarged.
941839
Make sure you don't have a lens cap blocking the other end.  Try aiming at distant objects, not close ones.  It may be that it is focussed for eyes that have a different tolerance than yours, so trying working the focus knob.  Failing to accomplish anything, I suggest you contact the nearest planetarium or science center and ask for help.  If they can't help, they should know members of a local astronomy club who can.
940059
the resolution is limited by diffraction, ie diffraction limit.\nd=1.22*wavelength*f/a wavelength=c/freq of light ~ c/5x10^14Hz =500nm, a=diamter of telescope =2.4m, f focal length = distance to pluto, to be in focus\nso the smallest feature size is : 1.22* 500nm*39.537 AU *149 598 000 000 m/AU /2.4m=1503308 m ~1500km, so not really\n\nexcerpt from telescopes article on wiki: "The phenomenon of optical diffraction sets a limit to the resolution and image quality that a telescope can achieve, which is the effective area of the Airy disc, which limits how close two such discs can be placed. This absolute limit is called the diffraction limit [ ...]. This limit depends on the wavelength of the studied light (so that the limit for red light comes much earlier than the limit for blue light) and on the diameter of the telescope mirror. This means that a telescope with a certain mirror diameter can resolve up to a certain limit at a certain wavelength. If greater resolution is needed at that wavelength, a wider mirror has to be built or aperture synthesis performed using an array of nearby telescopes."
976726
It depends on the length of the mirrors.
638048
For spherical mirrors:\n\n1/p  +  1/q  =  1/f\n\np = distance of the object from the mirror\n\nq = distance of the image from the mirror\n\nf = focal length of the mirror = half of the radius of the spherical mirror.\n\nq is positive if the image is formed in front of the mirror\n\nf is positive for concave mirror. Concave mirrors; imagine your inside a supperdome and the ceiling is one big mirror. Then the ceiling is a concave mirror. If you are parachuting and the roof of the superdome is one big mirror then that is a convex mirror, its f will be negative.
1097369
My personal reccomendation for a beginner with limited funds would be to get reflector on a dobsonian mount.  That is the type You move yourself.  Motorized mounts are very nice but they are costly.  Of most importance make sure the tripod and mount are sturdy.  Since a telescope is used to magnify - it will magnify the slightest movement and make the image blurry.  Incidently a Telescope does not magnify.  it only collects light to make the image brighter.  it is the function of the eyepiece to magnify.  I would suggest that you go to the website www.Astronomics.com.  They have been in business a long time and are very dependable and helpful.  They stand behind what they sell.  I have purchased scopes, eyepieces and filters from them over the years and am completly satisfied.  They have a site "how to choose a telescope"  Which you can download.  If You have further questions You can call them toll free and talk to someone who can help You.  Astronomy is a facinating hobby or even a lifetime occupation and the sooner You begin the better.  Also if there is an astronomy club in your area they are usually quite happy to share their knowledge with others.  They usually have "star parties"or viewing sessions and are glad to have visitors.   This would give You a chance to look through different types of scopes before investing in one.
180255
The only way that I know to do this with a normal telescope is to compare the star with others nearby of known magnitude and try to decide if it's brighter or dimmer until you find the same.\n\nOtherwise you'd need to measure the amount of light that comes from it, and I think you need computers to do that.\n\nThe magnitude scale is exponential, so deciding a magnitude ain't that simple. (ie a star of magnitude +2 is ten times brighter than a star of magnitude +3)
892778
I think maybe the separation is smaller than the resolving power of my eyes rather than the angular separation of my eyes. So I can't resolve the two sources and just see one bright star. \n\nBest of luck - Mike
294534
Locate the Aargon Blackbox demo. I downloaded this demo from the internet a few years ago when we studied optics. It is a great game where the kids are given an input location for a laser and based on the output location they have to discover where mirrors, lenses, etc are located. It is lots of fun.
350944
This sounds like a homework question?  Maybe I shouldn't give you the whole answer, so you can learn something on your own.\n\nYou are describing a Cassegrain telescope.  You can use the mirror formula to calculate the image plane for the first optic (the concave mirror) and then use that as the object plane for the second optic (the convex mirror) to get your final focal image plane.\n\nMirror Equation:  (1/So) + (1/Si) = -2/R\n\nSo = object plane (distance from object to mirror)\nSi = image plane (distance from image to mirror)\nR  = radius of curvature of mirror\n\nThe hardest part of these calculations is to use the right sign convention and to remember that the stars (initial object plane) can be treated as at infinity.
167535
If your telescope has a finder scope (a much smaller telescope mounted on the main telescope) stick with observing objects that you can locate in it. In order to observe more distant objects that you can't see with either your naked eye or the finder scope, you'll need to learn about the celestial coordinate system (right ascension and declination) There are hundreds of fascinating objects that even smaller telescopes can bring into your vision, but can't be easily located without knowing their celestial coordinates and how to locate those coordinates.
874618
I came up with a magnification of about 16\n\nThis interactive website will calculate what you need ==>http://www.csgnetwork.com/telescopemagcalc.html
920243
Make a Simple Telescope\nYou will need the following: \ntwo magnifying glasses - perhaps 1 - 1.5 inches (2.5-3 cm) diameter (it works best if one is larger than the other) \na cardboard tube - paper towel roll or gift-wrapping paper roll (it helps if it is long) \nduct tape \nscissors \na ruler, yard stick, or tape measure \nsheet of printed paper - newspaper or magazine will do \nTo assemble your telescope, do the following: \nGet the two magnifying glasses and a sheet of printed paper. \nHold one magnifying glass (the bigger one) between you and the paper. The image of the print will look blurry. \nPlace the second magnifying glass between your eye and the first magnifying glass. \nMove the second glass forward or backward until the print comes into sharp focus. You will notice that the print appears larger and upside down. \nHave a friend measure the distance between the two magnifying glasses and write the distance down. \nCut a slot in the cardboard tube near the front opening about an inch (2.5 cm) away. Do not cut all the way through the tube. The slot should be able to hold the large magnifying glass. \nCut a second slot in the tube the same distance from the first slot as your friend wrote down. This is where the second magnifying glass will go. \nPlace the two magnifying glasses in their slots (big one at front, little one at back) and tape them in with the duct tape \nLeave about 0.5 - 1 inch (1 - 2 cm) of tube behind the small magnifying glass and cut off any excess tube remaining. \nCheck to see that it works by looking at the printed page. You may have to play slightly to get the exact distances between the two glasses right so that the image comes to a focus. \nWith your telescope, you should be able to see the moon and some star clusters as well as birds, etc. \n\n+++++++++++++++++++++++\n\nMake a Simple Microscope\nYou can make a simple microscope by using magnifying glasses and paper: \nGet two magnifying glasses and a sheet of printed paper. \nHold one magnifying glass a short distance above the paper. The image of the print will look a little bit larger. \nPlace the second magnifying glass between your eye and the first magnifying glass. \nMove the second glass up or down until the print comes into sharp focus. You will notice that the print appears larger than it does in the first magnifying glass. \n\nI've included two links below for this and other info.\n\nMyst
1139401
Due to atmospheric interference, it would not be possible to see any mad made object left on the moon from a telescope on the surface of Earth.\nHowever, there is a very powerful, Earth orbiting, telescope which is free from atmospheric distortions…the Hubble space telescope.  However, even this telescope, as powerful as it is, could not possibly see the flag left on the moon.\n\nUsing a little math and common sense, it would not nearly be possible to see the flag on the moon with the Hubble space telescope.\n\nFirst, let’s get some basic facts straight.\nThe Diameter of the Hubble telescope is 2.4 meters and the distance from the Earth to the moon (on average) is about 3.84 E8 meters.\n\nPretty much the only thing limiting what Hubble can and cannot resolve is diffraction through a circular aperture (i.e. how light waves interact with each other when they get to Hubble's mirror.\nThe minimum angle which a circular aperture can resolve is given by the formula,\nTheta_min = 1.22 Lambda / D\nwhere Theta min is the minimum angle, Lambda is the wavelength of light we are using, and D is the diameter of the opening.\n\nIf we assume we are using light at 500 nm (roughly the middle of the visible spectrum) and we know that Hubble's diameter is 2.4 meters, we can find the minimum angle to be,\nTheta_min = 2.54 E-7 radians.\nThis is quite a small angle by Earthly standards, but will it compare to the angle to the flag on the moon?...we'll see.\n\nHere is where I have to make an assumption, but it is a very reasonable assumption and one that will assure us that out answer is correct. Watching the moon landing videos, one can see that the astronauts placed a moderately sized flag on a pole on the moon. Although I don’t know the exact dimensions of the flag, I can assure you, it was definitely no bigger than 10 ft. But for the sake of argument and to make the numbers easier, let’s assume it was 10 feet (~3 meters).\nIf the distance between the flag and Hubble is the same (about) as the distance from the Earth to the moon, then we can calculate the angle between the top of the flag and the bottom of the flag pole as seen by Hubble orbiting Earth. The angle comes out to be about, 7.81 E-9 radians, about 30 times SMALLER than the absolute minimum angle Hubble can resolve...and this is if we assume that the flag is 10 ft, which it obviously is smaller than that in reality.\n\nPlus, Hubble was specifically designed to look at VERY distant object. Although the moon is far away, it might as well be right next to us compared to the stars/galaxies/.. Hubble is supposed to be looking at. Therefore, I don’t know exactly how it will respond looking at such a close and bright object.\n\nOne this is sure through, you could not see the flag, even with one of the best telescopes ever built operating perfectly under ideal conditions using visible light.
816306
What do you need?  There are several types.  Newtonians, invented be Isaac Newton in 1673.  They have a primary mirror with a parabolic shape whose size is what is quoted when the telescope's size is mentioned.  The secondary mirror is small, flat, and angled to send the image to an eyepiece (or camera) mounted on the side of the tube.\nThe Cassegrainian (invented by Cassegrain!) has a hole in the primary mirror, and the image is reflected by the secondary through the hole to the eyepiece mounted on the end of the tube.  Most large reflectors today are this type.\nCoude' (from the French for elbow, not the inventor's name) has three mirrors, and the image is sent off to the side.\nSchmidt or Maksutov (invented during World War 2) has a lens at the top of the tube, plus the mirrors usually in the Cassegrain arrangement.\nNewtonians tend to be cheapest, Schmidt/Maksutov the most expensive.\nCheck wikipedia under each name for more details.