Hi Puneet,

Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot both be known to arbitrary precision. That is, the more precisely one property is known, the less precisely the other can be known. This is not a statement about the limitations of a researcher's ability to measure particular quantities of a system, it is a statement about the nature of the system itself as described by the equations of quantum mechanics. According to the uncertainty principle, it is, for instance, impossible to measure simultaneously both position and velocity of a microscopic particle with any degree of accuracy or certainty.In quantum mechanics, a particle is described by a wave. The position of the particle is regarded as being where the wave amplitude is greatest and the momentum is determined by the wavelength.The uncertainty principle can be restated in terms of measurements, which involves collapse of the wavefunction.