Characteristic distance at which quantum gravitational effects are significant, Planck length, can b

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1.Units, Dimensions and Measurement

hard

The characteristic distance at which quantum gravitational effects are significant, the Planck length, can be determined from a suitable combination of the fundamental physical constants $G, h$ and $c$ . Which of the following correctly gives the Planck length?

A

$G^2hc$

B

${\left( {\frac{{Gh}}{{{c^3}}}} \right)^{\frac{1}{2}}}$

C

${G^{\frac{1}{2}}}{h^2}c$

D

$Gh^2c^3$

(JEE MAIN-2018)

Solution

Plank length is a unit of length

$I_p\,= 1.616229\times10^{-35}\,m$

${l_p} = \sqrt {\frac{{hG}}{{{c^3}}}} $

Standard 11

Physics

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