Why Heisenberg principalis not applicable for macroscopic objects?
Heisenberg uncertainty principle involves Planck's constant (h) which is so small that the uncertainties in position and momentum of even quiet small (not microscopic objects) objects are far too small to be experimentally observed. For microscopic phenomena such as atomic processes, the displacements and momentum are such that the uncertainty relation is critically applicable. So, the uncertainty principle is significant only on the atomic scale because of the small value of h in everyday units.
You have rated this answer /10