Question:
Heisenberg's Uncertainty Principle says that the product of the error in the measurement of a particle's momentum and the error in the measurement of a particle's position must be at least Planck's constant divided by $4\pi$. Suppose the error in the measurement of the momentum of a particle is halved. By how many percent does the minimum error in the measurement of its position increase?

Answer:
Since the minimum position error and the momentum error are inversely proportional, halving one doubles the other, or increases it by $\boxed{100\%}$.