Find the wavelength of the particle

AI Thread Summary
To find the wavelength of a particle accelerated by a potential difference V, the de Broglie wavelength formula λ = h/mv is relevant, where m is the relativistic mass. The kinetic energy gained from the potential difference is converted into kinetic energy of the particle, expressed as 0.5mv². There is confusion about whether the particle maintains a constant speed after acceleration or continues to accelerate. Clarification on the relativistic effects is needed, as the discussion indicates a lack of depth in understanding these concepts. Understanding these principles is essential for solving the problem correctly.
fluidistic
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Homework Statement


I'm not even sure the problem is about matterwave:
A particle of mass m and charge e is accelerated by a potential difference V. Find the wavelength of the particle. Show that this result agrees with the classical one when the non relativistic limit is taken.

Homework Equations


Not sure, but I think that \lambda _B=\frac{h}{mv} where m is the relativistic mass, i.e. m=\gamma m_0.
Maybe F=qE?

The Attempt at a Solution


I'm not really sure how to find the motion equation of the particle and I need its velocity in order to calculate its de Broglie's wavelength. F=qE.
\Delta V =\int _A^b \vec E d \vec l... I don't go anywhere that way.
I've no idea what I'm missing.
 
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The energy produced by the pd is Ve, which is converted into ke of the particle (0.5mv2).
 


rock.freak667 said:
The energy produced by the pd is Ve, which is converted into ke of the particle (0.5mv2).

Thank you. Ah, very similar to an exercise I started 2 days ago and you helped me...
However isn't the kinetic energy worth c^2 (m-m_0)? Furthermore that would give a constant kinetic energy while they state "accelerated". Do they mean accelerated up to a speed v and then the particle maintains this speed constantly?!
 


fluidistic said:
Do they mean accelerated up to a speed v and then the particle maintains this speed constantly?!

I believe that is what it meant. I am not sure about the relativistic aspect though (never learned about it in depth).
 


rock.freak667 said:
I believe that is what it meant. I am not sure about the relativistic aspect though (never learned about it in depth).

Thank you for all your help.
 
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