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Homework #3
•Question 1   RADIO photons have the lowest energy.
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•Question 2   The thickness of a plastic freezer storage bag is roughly 0.1 mm. How many wavelengths of red light is this?
 140 = 0.1mm/7000Angstroms.
 
•Question 3   ALL statements are true.
 
•Question 4   Compared to gamma rays, radio waves travel at the same speed!   
• Question 5   Calculate wavelength/diameter for each, pick the smallest value.
a.A 2.3 meter telescope operating at 2 microns (like WIRO):  9x10-7
•b.The Hubble Space Telescope (2.5 meter) at 150 nanometers: 6x10-8
•c.The Very Large Array (36 km) at 43 GHz (0.65 cm):   1.8x10-7
•d.The 10-meter Keck telescope at 500 nanometers: 5x10-8
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•Question 6   All statements are true.
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•Question 7   The correct order of increasing photon energy:
   Radio -- Infrared - optical -- Ultraviolet -- X-ray -- Gamma Rays