Saturday, 11 February 2017

Physics Formulas and terms in Quantum Physics

Physics Formulas and terms in Quantum Physics
Quantum physics is one of the most interesting branches of physics, which describes atoms and molecules, as well as atomic sub-structure. Here are some of the formulas related to the very basics of quantum physics, that you may require frequently.
De Broglie Wave
De Broglie Wavelength:

λ = h/p
where, λ- De Broglie Wavelength, h - Planck's Constant, p is momentum of the particle.
Bragg's Law of Diffraction:

2a Sin θ = nλ
where
a - Distance between atomic planes
n - Order of Diffraction
θ - Angle of Diffraction
λ - Wavelength of incident radiation

Planck Relation

The plank relation gives the connection between energy and frequency of an electromagnetic wave:    E = hv = hω/2π
where
h is Planck's Constant,
v the frequency of radiation and
ω = 2πv
Uncertainty Principle
Uncertainty principle is the bedrock on which quantum mechanics is based. It exposes the inherent limitation that nature imposes on how precisely a physical quantity can be measured. Uncertainty

relation holds between any two non-commuting variables. Two of the special uncertainty relations are given below.
Position-Momentum Uncertainty

What the position-momentum uncertainty relation says is, you cannot predict where a particle is and how fast it is moving, both, with arbitrary accuracy. The more precise you are about the position, more uncertain will you be about the particle's momentum and vice versa. The mathematical statement of this relation is given as follows:   Δx.Δp h/2π
where Δx is the uncertainty in position and Δp is the uncertainty in momentum.

Energy-Time Uncertainty

This is an uncertainty relation between energy and time. This relation gives rise to some astounding results like, creation of virtual particles for arbitrarily short periods of time! It is mathematically stated as follows:  ΔE.Δt h/2π
where ΔE is the uncertainty in energy and Δt is the uncertainty in time.