Question

Why is the uncertainty principle not apparent for macroscopic objects?

Answer 1

Therefore, macroscopic objects does not obeys the uncertainty principle. The same cannot be said of microscopic objects because their wave-like properties become dominant. It's not possible to get a clear value of position and momentum at the same time for a wave, hence the uncertainty principle comes into play.

Answer 2

By Heisenberg's principle,
∆x.∆p >=h/(4π)
Where ∆p=m∆v [For slow moving particles wrt light speed]
From the formula, with increase in momentum, the uncertainty of its position decreases. So for maximum position certainty, the momentum should be very low.
Now take mass m as low as 1gm and change in velocity ∆v 0.01m/s so that the momentum is very low.
Given, Planck's constant h=6.62x10^-34 SI units.
Now calculate the uncertainty in position yourself. See the magnitude of the value. You have got the answer yourself.
Still not satisfied??? Take lower values of m & ∆v and calculate the uncertainty in position each time.
Now take m=9.1x10^-31 kg and ∆v=2.2x10^6 m/s and calculate the uncertainty. Its still small, in the order of angstrom, but it is a huge uncertainty for the subatomic particles.
Hope it helps...:)