Heisenberg Uncertainty — Practice Quiz

Question 1

An electron's position is measured to within Δx = 0.1 nm. Minimum uncertainty in momentum:

Accepted Answer

5.3 × 10⁻²⁵ kg·m/s

Answer

5.3 × 10⁻²² kg·m/s

Answer

5.3 × 10⁻²⁴ kg·m/s

Answer

5.3 × 10⁻²⁰ kg·m/s

Question 2

Heisenberg's uncertainty principle is a consequence of:

Accepted Answer

Wave nature of matter

Answer

Measurement disturbance

Answer

Classical mechanics

Answer

Coulomb's law

Question 3

The principle does NOT apply to:

Accepted Answer

It is universal — applies to everything

Answer

Electrons

Answer

Photons

Answer

Atoms

Question 4

An excited atomic state has lifetime 10⁻⁸ s. Its energy uncertainty is approximately:

Accepted Answer

~5 × 10⁻⁸ eV

Answer

~ 10⁻⁸ eV

Answer

~5 × 10⁻²⁷ eV

Answer

~10 eV

Question 5

Why are atoms stable per the uncertainty principle?

Accepted Answer

Confining an electron to nuclear-sized Δx would require infeasible momentum → energy

Answer

Electrons orbit safely

Answer

Photons absorb

Answer

Pauli exclusion