Magnetic Field of a Current Loop: Consider two current-carrying circular loops. Both are made from one strand of wire and both carry the same current, but one has twice the radius of the other. If the magnetic field strength at the center of the smaller loop is B, what is the magnetic field strength at the center of the larger loop?
A. 8B
B. 4B
C. 2B
D. B/2
E. B/4
Answer: D
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The "top-down" approach to creating artificial life starts
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A light ray enters a glass enclosed fish tank. From air it enters the glass at 20° with respect to the plane of the surface and then emerges into the water
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