Try to think about this question and when all your knowledge has been used, search wiki. for this experiment and read Bohr's remark to this experiment.Imagine a particle A to be a rest hence the center of mass is at rest and the velocity of center of mass and hence the momentum is 0. The particle A decomposes to two particles B and C which move at 180degree angle.What you do is that you make the uncertainity of position of B as small as possible and let the momentum have a huge uncertainity -who cares.And then you measure the momentum of C very carefully neglecting the position of C. The uncertainity of position of B is z then minimum uncertainity in momentum is of order h/z. But momentum of B=momentum of C hence as we can measure the momentum of C with an uncertainity smaller than h/z we can in a way defy uncertainity principle but which is true........so where lies the fallacy?

Radhika Batra , 11 Years ago

Grade 11