# De Broglie Wavelength Thought Problem

1. Apr 2, 2014

1. The problem statement, all variables and given/known data
A) Find the wavelength of an Ewok that has a mass of 50kg and is Running on Edor where 'h' id 1000Js at a velocity of 0.5m/s

Yes the value of h to be used is 1000.

B) What would the implications of him running be?

2. Relevant equations
$\lambda=\frac{h}{p}$

3. The attempt at a solution
Part A: $\lambda=\frac{h}{p} \\ \lambda=\frac{1000}{50 \times 0.5}=40m$

For part B: I wasn't quite sure to be honest, but surely with such a large wavelength and running, he would be "interfering" with himself quite badly ?

Last edited: Apr 2, 2014
2. Apr 2, 2014

### daqddyo1

I don't know where you got the value for Planck's constant but it is not correct. The accepted value is 6.62606957 × 10−34 joule∙second. Use 6.626x10-34 and your calculated DeB λ will be much smaller.

3. Apr 2, 2014

This was a thought experiment, the value to be be used for the question is 1000Js. Its an imaginary scenario. A made up example by our lecturer to get us to think what would the implications be.

4. Apr 2, 2014

### Staff: Mentor

Does anything happen to the de Broglie wavelength when he starts running?

5. Apr 2, 2014

Ah, yeah. The perticular bit of coursework which had this question on has already been handed in but wanted to know if I got it correct or not, plus its interesting to think about.

I assumed they meant constant velocity, but now thinking about it for part B it probably makes sense to assume he is not running at a constant velocity. But yes, if he speeds up then v will get bigger and the wavelength would therefore get shorter and the other way around if he slowed down.

6. Apr 2, 2014

### Staff: Mentor

I wouldn't consider 0.5 m/s running, even for an Ewok

7. Apr 2, 2014