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Ananya Shree

Class 11th
Physics
2 years ago

If Planck’s constant (h) and speed of light in vacuum (c) are taken as two fundamental quantities, which of the following can, also, be taken to express length, mass, and time in terms of the three chosen fundamental quantities? a) mass of the electron (me) b) universal gravitational constant (G) c) charge of the electron (e) d) mass of proton (mp)

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Muskan Anand

2 years ago

(h)=[T−1][ML2T−2]​=[LT−1] for mass, let M=CahbGc [ML0T0]=[LT−1]a[ML2T−1]b[M−1L3T−2]c Using the principle, b−c=1⟶(1) a+2b+3c=0⟶(2) −a−b−2c=0⟶(3) So, a=2−1​ also a=21​ Hence, M=C1/2h1/2G−1/2⇒M=GCh​​ Similarly, for length L=C3hG​​  and  T=C5hG​​ ∴   Plank's length =C3Gh​​ ; Plank's time =C5Gh​​  and  Plank's Mass =GCh​​

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