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Physics_Student
Aug16-04, 10:16 AM
Simple question;

For an electron, what is its velocity after it has been accelerated through 50V?

I thought about equating 50eV to KE, but I know thats the wrong way, any ideas?

Nav

vanesch
Aug16-04, 10:20 AM
For an electron, what is its velocity after it has been accelerated through 50V?
I thought about equating 50eV to KE, but I know thats the wrong way, any ideas?


Why is that wrong ??

cheers,
Patrick.

Physics_Student
Aug16-04, 10:21 AM
dunno, it doesnt feel right? is that way the correct way?

cepheid
Aug16-04, 11:56 AM
It's correct because an electron volt is defined as the energy gained by an electron (elementary charge) when accelerated through a potential difference of 1 V. So 50V imparts 50eV to the electron, which is equal to its final kinetic energy. From that you can easily calculate it's final velocity.

Gonzolo
Aug16-04, 11:58 AM
Don't forget to consider initial energy, velocity, direction etc.

Nenad
Aug17-04, 11:05 AM
abd dont forget to calculate that using relativistic Kinetic Energy.

zefram_c
Aug17-04, 11:32 AM
dont forget to calculate that using relativistic Kinetic Energy I don't think that's needed here; the electron's rest mass is about 0.5MeV and we're talking a KE of 50eV.