(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

What is the De Broglie wavelength of an electron with KE= 8.5 eV?

2. Relevant equations

λ=h/p

KE=0.5mv^{2}

p=mv

3. The attempt at a solution

I converted 8.5 eV into joules:

8/5 eV × 1.602e-19 J = 1.3617e-18

Then used it for KE to solve for v:

I got 1729006.11

Used v to get p:

9.11e-31 × 1729006.11 = 1.575e-24

Used p to get λ:

6.63e-34/1.575e-24

And received λ= 4.209e-10

The answer required is on the order of picometers, and when I convert it to pm the answer is wrong. Entering it as it is also comes up wrong.

Sorry I use excessive sigfigs, my homework is through the Connect system for my textbook and there is a VERY SMALL margin of error so you always have to keep a bunch of extra or the answer might come up as wrong if you round too early.

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# Homework Help: De Broglie Wavelength from KE

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