Chapter 34: Q28CQ (page 1237)
Discuss whether you think there are limits to what humans can understand about the laws of physics. Support your arguments.
Short Answer
In terms of what humans can grasp, the laws of physics have no bounds.
Chapter 34: Q28CQ (page 1237)
Discuss whether you think there are limits to what humans can understand about the laws of physics. Support your arguments.
In terms of what humans can grasp, the laws of physics have no bounds.
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Discuss the possibility that star velocities at the edges of galaxies being greater than expected is due to unknown properties of gravity rather than to the existence of dark matter. Would this mean, for example, that gravity is greater or smaller than expected at large distances? Are there other tests that could be made of gravity at large distances, such as observing the motions of neighbouring galaxies?
A section of superconducting wire carries a current of\({\rm{100 A}}\)and requires\({\rm{1}}{\rm{.00 L}}\)of liquid nitrogen per hour to keep it below its critical temperature. For it to be economically advantageous to use a superconducting wire, the cost of cooling the wire must be less than the cost of energy lost to heat in the wire. Assume that the cost of liquid nitrogen is\({\rm{\$ 0}}{\rm{.30}}\)per litre, and that electric energy costs\({\rm{\$ 0}}{\rm{.10}}\)per KW·h. What is the resistance of a normal wire that costs as much in wasted electric energy as the cost of liquid nitrogen for the superconductor?
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