### A question about Planck length and Planck time

by **curiosity** on October 13th, 2016, 9:46 pm

If I convert one second of sidereal time into Planck time, then convert 299 792 458 meters into Planck length, why dont I get identical answers? There are clocks now, that are so accurate, that one meter of length can be given as a time (when using the speed of light as a common denominator.) So why don't the numbers add up, when the distance that light travels in one second is calculated in planck units ? I Have always been under the impression that the laws of physics hold true, right down to the Planck length, which is obviously wrong. Could somebody clarify this problem for me? If one Planck length is the distance light travels in one Planck time, surely

the total units in each measurement should be the same?