Physics · 2018
JEE Main · 15 April 2018, Shift 2 · Q1
The characteristic distance at which quantum gravitational effects are significant, the Planck length, can be determined from a suitable combination…
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, $\displaystyle \hbar$ and c. Which of the following correctly gives the Planck length ?
Official answer
(4)
$\displaystyle \left(\frac{\mathrm{G} \hbar}{\mathrm{c}^3}\right)^{1 / 2}$
More from Units and Dimensions
- The de-Broglie wavelength associated with a particle of mass m and energy E is h / √(2 m E). The dimensional formula for Planck's constant is:2024
- If E and H represents the intensity of electric field and magnetising field respectively, then the unit of E/H will be:2021
- If B is magnetic field and μ_0 is permeability of free space, then the dimensions of (B / μ_0) is2025
- L, C and R represents physical quantities inductance, capacitance and resistance respectively. The dimensional formula M L^2 T^-4 A^-2 corresponds to…2026
- If current ( I ), kinetic energy ( K ) and charge ( Q ) are taken as the fundamental quantities, The dimensional representation of power will be:2022
- If the velocity of light c, universal gravitational constant G and Planck's constant h are chosen as fundamental quantities. The dimensions of mass…2023
- A quantity f is given by f=√((hc^5)/G) where c is speed of light, G universal gravitational constant and h is the Planck's constant. Dimension of f…2020
- A quantity x is given by ( IF v^2 / WL^4 )in terms of moment of inertia I, force F, velocity v, work W and Length L. The dimensional formula for x is…2020
JEE Main 2018 Physics question, with the answer from NTA’s final answer key. Where our answers come from.