Since 1983 the standard meter has been defined in terms of which of the following?
A)specific alloy bar housed at Sevres,France
B)wavelength of light emitted by krypton-86
C)distance from the Earth's equator to the North Pole
D)the distance light travels in a certain fraction of a second
E)None of the above

Question

Since 1983 the standard meter has been defined in terms of which of the following?​
A)specific alloy bar housed at Sevres,France
B)wavelength of light emitted by krypton-86
C)distance from the Earth's equator to the North Pole
D)the distance light travels in a certain fraction of a second
E)None of the above

Quizplus · Accepted Answer

Since 1983, the standard meter has been defined in terms of the distance that light travels in a certain fraction of a second (299,792,458 meters per second). This definition is known as the "speed of light" definition and has been adopted internationally as the standard metric unit of length.

Since 1983 the Standard Meter Has Been Defined in Terms