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Author Question: How is 21 cm radiation produced? What will be an ideal response? ... (Read 25 times)

chandani

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on: Jul 27, 2018
How is 21 cm radiation produced?
 
  What will be an ideal response?

Question 2

What is the approximate chemical composition (by mass) with which all stars are born?
 
  A) three quarters hydrogen, one quarter helium, no more than 2 heavier elements
  B) half hydrogen and half helium
  C) 98 hydrogen, 2 helium
  D) 95 hydrogen, 4 helium, no more than 1 heavier elements


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brittanywood

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Reply #1 on: Jul 27, 2018
Answer to Question 1

When the electron orbiting the proton for hydrogen flips its spin, the energy radiated has a wavelength of 21 cm., and is detected with radio telescopes.

Answer to Question 2

A


chandani

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Reply 2 on: Jul 27, 2018
YES! Correct, THANKS for helping me on my review

bassamabas

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Reply 3 on: Yesterday
Excellent

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