# How to get the quantity of Physical constants?

I need to get the quantity of gravitational constant: QuantityMagnitude[GravitationalConstant] why this is not work? Already load the PhysicalConstants package.

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QuantityMagnitude@UnitConvert[Quantity["GravitationalConstant"]] –  RunnyKine Nov 16 '13 at 3:05
@RunnyKine Great! –  van abel Nov 16 '13 at 3:07
you do not need to load the PhysicalConstants package –  becko Nov 27 '13 at 20:43
man its irritating the docs just say "physical constant functionality is built into mathematica" without providing any clue how to access. Even if you find the Quantity page it doesn't say anything about physical constants. –  george2079 Apr 4 at 15:58

QuantityMagnitude@UnitConvert[Quantity["GravitationalConstant"]]