As per [Wikipedia](https://en.wikipedia.org/wiki/International_System_of_Units), the new definition of kilogram is, “The kilogram is defined by setting the [Planck constant](https://en.wikipedia.org/wiki/Planck_constant) *h* exactly to 6.62607015×10−34 J⋅s (J = kg⋅m2⋅s−2), given the definitions of the metre and the second.”, while that for Kelvin is, “The kelvin is defined by setting the fixed numerical value of the [Boltzmann constant](https://en.wikipedia.org/wiki/Boltzmann_constant) *k* to 1.380649×10−23 J⋅K−1, (J = kg⋅m2⋅s−2), given the definition of the kilogram, the metre, and the second.”
These are the only two, in the list of 7 which don’t help form an idea of what that quantity actually is.
In: Physics
One way of looking at it is that if you convert a kilogram of mass into a single photon of energy, it would have a frequency equal to the reciprocal of the Planck constant.
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