Compare an amateur telescope of 100 mm (a typical &quot;4-inch&quot; telescope, usually a refractor) with that of the Keck telescope, which is 10...
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# Stuck on questions 2 and 3, see attachment ATTACHMENT PREVIEW Download attachment Screen Shot 2020-01-06 at 4.14.02 PM.png 2. Compare an amateur telescope of 100 mm (a typical &quot;4-inch&quot; telescope, usually a refractor) with that of the Keck telescope, which is 10 meters across. [Hint: Work in powers often; &quot;2 decimals&quot; means after the decimal point in powers of ten notation.] (a) Area of 100-mm objective in mm: mm [Write in scientific notation and round to 2 decimals; same for part b] (b) Area of 100-mm objective in m': m' (Careful! Note the conversion from millimeters to meters. Working with powers of ten can make this step easier. Hint: How many mm in 1 meter? How many mm in 1 m ?) [Round to 2 decimals] (c) Area of 10-m Keck objective: m [Write answer in scientific notation and round to 2 decimals] (d) 10-m objective collects times the light of a 100-mm objective [Round to nearest whole number] (e) The answer to (d) represents how many magnitudes? (Hint: Look for the x&quot; function on a scientific calculator. If (2.512) = 100 and represents 5 magnitude steps, then how many steps does the answer to d represent? If 100 = 10 x 10 or 102, then how many powers of ten is the answer to d?) 3. A quicker way to calculate light-gathering power is to use the formula: LGP LGP D. [ Hint: Don't forget that on the right side the values are squared after being divided.] where LGPA and LGPe are the light-gathering powers of A and B, respectively, and DA and De are the diameters of objectives A and B. respectively. If the human eye has a diameter of 8 mm (actually the pupil of the eye), and we have both a 50-mm telescope and a 203-mm telescope, how much more light will the telescopes gather than our eye? [Round answers to nearest whole number] (a) LGPsom/LGPeye = times more light (b) LGP20 mm/LGPye = times more light

2. (a) Area of 100-mm objective is 7 . 8 5 1 0 3 m m 2 (b) Area of 100-mm objective in m 2 is ... View the full answer

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