Week 9 Infinite Square Well & Momentum Flashcards Preview

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Flashcards in Week 9 Infinite Square Well & Momentum Deck (10)
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describe the infinite square well scenario

a particle is restricted to a region between 0 and L and only travels in one direction


what can be observed of a particle with definite energy in this square well

it's Ψ is confined to exact discrete values


what is the normalisation for Ψ when restricted to a region of length L

Ψ(n) = Asin(nπx/L)
A is some complex number


what does the wave function tell us about a particle for quantum physics

everything we need to know allowing us to calculate all properties of the particle


what are the two p related equations that involved interchanging h with ħ

p = ħk
p = h/λ


define the differential operator for momentum

p(hat) = -ih(bar) d/dx


what is the equation relating p and p(hat)

pΨ = p(hat)Ψ


what is the uncertainty is momentum equation

Δp = sqrt[


^2 ]


what is the Heisenberg Uncertainty principle equation and what is the important condition

ΔxΔp = αh(bar) / 2
α >= 1


what does the uncertainty principle essentially state

As Δx tends to infinity Δp tends to 0 in order to combat this and the reverse is true. Therefore it is impossible to know both the position and momentum of a particle to arbitrary accuracy