All moving objects which are observed around move along definite path, like a train or a ball thrown in the aire etc So, their position and velocity (and hence linear momentum) can be measured accurately at any instance of time. However, the same cannot be said for subatomic particles, presumably because these species are too small to be seen normally. So, Heisenberg enunciated a principle about the uncertainties in simultaneous measurement of position and momentum (mass x velocity) of micro substances. The principle was based ont the fundamentals of dual nature of matter.
This principle states that "It is impossible to measure simultaneously the position and momentum ( and hence, velocity) of a small microscopic moving substance with absolute accuracy or certainty". If an attempt is made to measure any one of these two quantities with higher accuracy, the other becomes less accurate. So, mathematically, the product of the uncertainty in position (∆x) and the uncertainty in the momentum (∆p=m. ∆v where m is the mass of the particle and Av is the uncertainty in velocity) is equal to or greater than h/4T where h is the Planck' s constant. So, the mathematical expression for the Heisenberg' s Uncertainty Principle is simply written as
∆x × ∆p ≥ h/4π
∆x × m ∆v ≥ h/4π
∆x × ∆v ≥ h/4πm
Note that if m is large enough, the uncertainties ∆x and ∆v can be quite small and still satisfy the uncertainty principle For objects large enough to be seen, the uncertainties are small and one can easily describe their orbits. Thus, the orbit of a baseball and the orbit of the Earth are easily determinable. But, when one considers an electron or any other subatomic species, the uncertainties become significant.
It is important to remember that Heisenberg' s uncertainty principle is not applicable to macroscopic particles.
إرسال تعليق