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An alpha particle commonly has a speed of $15{,}000 \text{ km/s}$.

What is a reasonable value for the de Broglie wavelength of an alpha particle when considered as a matter wave?

$\lambda =2.65\times { 10 }^{ -14 }\text{ m}$

$\lambda =6.65\times { 10 }^{ -15 }\text{ m}$

$\lambda =4.15\times { 10 }^{ -4 }\text{ m}$

$\lambda =6.65\times { 10 }^{ -12 }\text{ m}$