Author Question: The SI unit of length, the meter, is currently defined A) as 10-7 of the distance from the North ... (Read 79 times)

littleanan · **on:** Jul 27, 2018

The SI unit of length, the meter, is currently defined

A) as 10-7 of the distance from the North Pole to the equator along a meridian running through Paris.
B) as the length of the path traveled by light in a vacuum during 1/299792485 s.
C) by the President's foot.
D) as the distance between two marks on a metal bar make of a platinum-iridium alloy kept at the National Bureau of Standards.
E) 1,553,164.1 wavelengths of red cadmium light in dry air at 25C.

Question 2

What is the primary topic of study in quantum mechanics?

A) the role played by atoms in astronomy
B) subatomic particles and the forces with which they interact
C) the mechanical movements of the heavens
D) the role of relativity in astronomy