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posted by  d0ve on 7/22/2008 2:00:12 AM  |  status: Live  

The de Broglie Relation

Course Textbook Chapter Problem
General Physics College Physics (8th) by Young N/A N/A
Question Details:
Part A
Find the de Broglie wavelength lambda for an electron moving at a speed of 1.00 \times 10^6 \; {\rm m/s}. (Note that this speed is low enough that the classical momentum formula p=mv is still valid.) Recall that the mass of an electron is m_{\rm e} = 9.11\times 10^{-31}\; {\rm kg}, and Planck's constant is h = 6.626 \times 10^{-34}\; {\rm J \cdot s}.
Express your answer in meters to three significant figures.
  lambda  =
  \rm m

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Part B
Find the de Broglie wavelength lambda of a baseball pitched at a speed of 44.2 m/s. Assume that the mass of the baseball is 0.143 \;{\rm kg}.
Express your answer in meters to three significant figures
  lambda  =
  \rm m

submitshow answer
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posted by palmreader on 7/22/2008 3:32:49 AM  |  status: Live
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d0ve's comment:
"thanks a bunch!"
Response Details:
p = h/λ = mv

a)    λ = h/mv = 6.626x10-34Js / (9.11x10-31kg * 1.00x106ms-1)
                     = 7.27x10-10m

b)   λ = h/mv = 6.626x10-34Js / (0.143kg * 44.2ms-1)
                    = 1.05x10-34m
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