General Knowledge · 2
In what year was the meter redefined based on the speed of light rather than a physical platinum bar?
Answer
1983
In 1983, the 17th General Conference on Weights and Measures redefined the meter as the distance light travels in a vacuum in 1/299,792,458 of a second, replacing physical prototype standards.
💡 Did you know?
The meter was redefined in 1983 using light speed rather than a platinum bar, making it the first measurement based purely on physics.
Other options people guess
- 1960
- 1889
- 1799
Topics
- measurement
- science
- history
- physics
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