Planck's Constant Digits

[dav2008]

OK, we all know theres tons of websites that give the digits of Pi and even e...But does anyone know how many digits we know Plancks constant to? Is experimentally the only way to determine it?

[Integral]

Unlike π and e, which are defined mathematically, h and c are experimental numbers so we do not know them to more digits then have been measured. h is sort of self limiting.

[Loren Booda]

NIST lists the CODATA concise form for Planck's constant as h=6.626 068 76(52) x 10-34 J s.

[dav2008]

Hm..Ive seen those parenthesis after constants in my textbook...What do they mean? It says something about like theyre not certain about those digits...is that right?

[Loren Booda]

()=uncertainty or experimental error(?)

[Integral]

Originally posted by Loren Booda
NIST lists the CODATA concise form for Planck's constant as h=6.626 068 76(52) x 10-34 J s.

The (52) is the error in the last digits, so

6.626 068 24 < h < 6.626 069 28