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Wavelength of an electron

  • #1

Homework Statement


What is the corresponding wavelength, in meters, of an electron moving at 1 m/s?
Velocity: 1 m/s
Planks Constant = 6.626 069 57 x 10^-34
Mass of electron = 9.109 382 91 x 10^-31
Momentum = unknown

Homework Equations


We need to find momentum to use De Broglie's equation.

Momentum = Mass * Velocity
De Broglie's Equation for finding the wavelength: λ = h/p
h being the planck constant


The Attempt at a Solution



My attempt.

Finding momentum : P = 9.109 382 91 x 10^-31 * 1 m/s
p = 9.109 382 91 x 10^-31
finding the wavelength
First divide the numbers WITHOUT the exponent
so 6.626 069 57/9.109 382 91 = 0.727 389 51
now exponents -34/-31
= -3 (I took out the extra steps)

final answer λ = 0.727 389 51 x 10^-3

is this correct?
 
Last edited:

Answers and Replies

  • #2
rude man
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1. First divide the numbers WITHOUT the exponent
so 6.626 069 57/9.109 382 91 = 0.727 389 51
now exponents -34/-31
= -3 (I took out the extra steps)

final answer λ = .0727 389 51 x 10^-3

is this correct?


No.
How did you get from 0.727 389 51 to .0727 389 51 ?
 
  • #3
No.
How did you get from 0.727 389 51 to .0727 389 51 ?
Oh crap ! MY bad human error it is a typo!
 
Last edited:
  • #4
rude man
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Oh crap ! MY bad human error it is a typo!
Thought so! But instructors mark off for those too! :smile:
 
  • #5
Thought so! But instructors mark off for those too! :smile:
Haha I will be more weary next time! So does the math look off? :tongue:
 
  • #6
rude man
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Math is fine.
 

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