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JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
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 \(Gh^2c^3\)
Answer & Solution
Correct Answer
(B) \({\left( {\frac{{Gh}}{{{c^3}}}} \right)^{\frac{1}{2}}}\)
Step-by-step Solution
Detailed explanation
Plank length is a unit of length \(I_p\,= 1.616229\times10^{-35}\,m\) \({l_p} = \sqrt {\frac{{hG}}{{{c^3}}}} \)
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