Describe reflection and refraction. How do these processes enable astronomers to build telescopes? Do these principles work equally well for ALL types of non-optical telescopes; i. e. those built to view the non-visible regions of the electromagnetic spectrum (radio, infrared, ultraviolet, x-ray, gamma)? Explain carefully by using at least two specific examples from the list of the five.
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Physics, 22.06.2019 00:30, WorkingButNotReally
Comedians like to joke that the reason we haven’t been visited by intelligent life from elsewhere in the universe is that aliens have been monitoring earth’s broadcasts of intellectually embarrassing tv programs, like gilligan’s island, fear factor, the jersey shore, and the jerry springer showand so consider us far too primitive to merit a visit. let’s check the assertion that aliens could have been receiving them. tv programs are broadcast at a frequency of about 100mhz with about 100kw of total power in 30frames per second, which emanatesroughly uniformly in all directions. assume that interstellar space transmits these broadcasts without attenuation. no matter how smart they are, aliens would require at least one photon per frame to interpret our signals. findthe number of photons per unit time per unit area reaching a receiver on a possible planet in the nearest star system, which is about 4 light-years away (a light-year is the distance light travels in a year). if aliens aimed a receiver or detector directly at earth, how big (in diameter) would it have to be to receive a photon per frame
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Physics, 22.06.2019 05:30, 444x4gang4
Because light travels in a straight line and casts a shadow, isaac newton hypothesized that light is
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Physics, 22.06.2019 08:30, lovebunfan
What is the primary force that suspension bridges use cables to hold their spans up? a. tension force b. resistance force c. normal force d. elastic force e. applied force
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Describe reflection and refraction. How do these processes enable astronomers to build telescopes? D...
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