Early in the 20th century, our galaxy was estimated to be:
A) about 100,000 ly in diameter.
B) about 35,000 ly (10 kpc) in diameter.
C) about 10 million ly in diameter.
D) not much larger than our solar system.
E) about 2.5 million ly in diameter.
B
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Indicate whether the statement is true or false
A soap bubble has an index of refraction of 1.33. What minimum thickness of this bubble will ensure maximum reflectance of normally-incident light having a wavelength of 530 nm?
A) 24.9 nm B) 76.9 nm C) 398 nm D) 99.6 nm E) 199 nm
If an object's acceleration is nonzero, its velocity must be __________
Fill in the blank(s) with correct word
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