Uncertainty Principle Using ΔEΔt ≥ ħ/2: a Laser Produces a Beam

question 60

Multiple Choice

Uncertainty principle using ΔEΔt ≥ ħ/2: A laser produces a beam of 4000-nm light. A shutter allows a pulse of light, 30 ps in duration, to pass. Which of the following is closest to the uncertainty in the energy of a photon in the pulse? (ħ = 1.055 × 10^-34 J ∙ s = 6.59 × 10^-16 eV ∙ s)

• A) 10^-6 eV
• B) 10^-5 eV
• C) 10^-4 eV
• D) 10^-3 eV
• E) 10^-2 eV

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Definitions:

Equilibrium

A state of balance or stability arising from the equal action of opposing forces.

Self-reinforcement

Administering rewards or punishments to oneself for meeting, exceeding, or falling short of one’s own expectations or standards.

Conscience

An inner feeling or voice viewed as a guide to the rightness or wrongness of one's behavior.

Superego

In Freudian psychoanalysis, the part of the psyche that acts as a moral center, incorporating the values and norms of society and acting as a counterbalance to the id.