Can someone explain significance of uncertainity princple , in detail ? the explanation written above did not strike me .

Heisenberg’s Uncertainty Principle: It is not possible to measure simultaneously both the position and velocity (or momentum) of a small particle with absolute accuracy or certainty. If position is measured accurately, there will be more error in the measurement of momentum. Conversely, if momentum is measured more accurately, the position will not be accurately known.

The product of the uncertainty in the position (x) and the uncertainty in the momentum (p = m.  where m is the mass of the particle and  is the uncertainty in velocity) is always constant and is equal to or greater than h/4∏, where h is Planck’s constant i.e., mathematical expression for the Heisenberg’s uncertainty principle is simply written as :

Significance of Heisenberg’s uncertainty principle  Heisenberg’s uncertainty principle has no significance in everyday life. Since in everyday life, we come across big objects only i.e, the objects which we can see with naked eye without altering their motion. As energy of the photon is insufficient to change the position and velocity of bigger bodies when it collides with them, the position and velocity of bigger bodies can be measured accurately. For example, the light from a torch falling on a running rat in a dark room neither changes the speed of the rat nor its direction i.e. position. But when we see microscopic things using light of photons then their position and velocity get disturbed by them. Hence, Heisenberg’s uncertainty principle holds good for all objects but it is of significance only for microscopic particles.

@ sujitguha,

Good answer! Your contribution to this forum is really appreciable. Keep posting!