Question

What is the value of Planck’s constant in S.I units?

Answer 1

Planck’s constant is a physical constant that associates the energy carried by a single photon to its equivalent frequency. It is denoted by h and measured using $J.s$(Joules second) in the SI system. The value of Planck’s constant is very important in quantum mechanics for determining various factors affecting the photoelectric effect, matter-wave equation, atomic structure, uncertainty principle, etc.

Complete answer:
Planck’s constant is defined as an essential constant which is the same as the energy of a quantum of electromagnetic radiation by its frequency. The value of Planck’s constant or value of$h$ is experimentally found out. The value of h is given in SI units as $h\; = {\text{ }}6.6260715 \times {10^{ - 34\;}}J.s$. The value of the Planck constant is applied in numerous applications including Planck’s equation. The energy-related with a photon is known by the product of the Planck constant $\left( h \right)$and its frequency. . For example, let’s only take the h value under various factors. Let us take the photoelectric effect, the famous Planck Einstein relation is given by$E = hf$. In atomic structure, Energy of ${n^{th}}$ orbit is given by ${E_n} = \dfrac{{ - h{C_0}{R_\infty }}}{{{n^2}}}$ and in the matter-wave equation we get the de Broglie wavelength as $\lambda = \dfrac{h}{p}$ and in the uncertainty principle we get $\Delta x.\Delta p \geqslant \dfrac{{\dfrac{h}{{2x}}}}{2}$

Note:
Quantum mechanics gives us that energy is switched and captivated indefinite quantities, known as “quanta.” $h$ which defines the size of those quanta, which can be imagined as packets of energy that are exchanged by matter. The Value of$h$ in Meter-Kilogram-Second $\left( {MKS} \right)$units is$$$$$$h; = {\text{ }}4.135667662 \times {10^{ - 15}};eV.s$and the value of$h$in the form of${E_p}.{t_p}$is given by$2{\text{ }}pi$$.