# 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 $\mathrm{G}, \mathrm{h}$ and $\mathrm{c}$. Which of the following correctly gives the Planck length?

Question:

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 $\mathrm{G}, \mathrm{h}$ and $\mathrm{c}$. Which of the following correctly gives the Planck length?

1. $\mathrm{G}^{2} \mathrm{hc}$

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

3. $\mathrm{G}^{\frac{1}{2}} \mathrm{~h}^{2} \mathrm{c}$

4. $\mathrm{Gh}^{2} \mathrm{c}^{3}$

JEE Main Previous Year Single Correct Question of JEE Main from Chemistry Laws of Motion chapter.

JEE Main Previous Year [Online April 15, 2018

Correct Option: 2

Solution:

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