Question

What does the Heisenberg Uncertainty Principle state that it is impossible to know?

Answer 1

Heisenberg Uncertainty Principle tells us that it is not possible to know with absolute precision the position AND the momentum of a particle (at microscopic level).
This principle can be written (along the `x` axis, for example) as :
`DeltaxDeltap_x>=h/(4pi)` (`h` is Planck's Constant)

Where `Delta` represents the Uncertainty in measuring the position along `x` or to measure the momentum, `p_x` along `x`.
If, for example, `Deltax` becomes negligible (uncertainty zero), so you know EXACTLY where your particle is, the uncertainty in its momentum becomes infinite (you'll never know where it is going next!!!!)!

This tells you a lot about the idea of absolute measurements and precision of a measurement at a microscopic level!!! (also because, at microscopic level, a particle becomes....a Wavicle!!!!)

Hope it helps!