Differentiate De Broglies Theorem

AI Thread Summary
The discussion centers on differentiating De Broglie's theorem, specifically the equation Px = h/λ. The differentiation process involves applying the chain rule, resulting in ΔPx = [-h/(λ^2)]Δλ. The differentiation is performed with respect to the wavelength λ. The method used is standard calculus, where the derivative of P with respect to λ is calculated as dP/dλ = (-h/λ^2). This illustrates the relationship between momentum and wavelength in quantum mechanics.
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Homework Statement



Someone has written down in some notes about differentiating DeBroglies Theorem.

They've started with Px =h/λ
(That's P sub x)

Then they've simply said, this differentiated is:

ΔPx = [-h/(λ^2)]Δλ

How have they done this? What method? What have they differentiated with respect to?

Thank you!

Homework Equations





The Attempt at a Solution

 
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respect to λ

P = h/λ

dP/dλ = (-1/λ^2) * h

dP = -(h/λ^2)dλ
 
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