How Does a Potential Difference Affect Kinetic Energy of a Charged Particle?

AI Thread Summary
A particle with charge -3e is accelerated through a potential difference of 200V, resulting in a change in kinetic energy. The relevant equation for calculating kinetic energy is E = qV, where q is the charge and V is the potential difference. The discussion clarifies that the mass of the particle is not needed to find the kinetic energy in this context. It emphasizes that the particle gains kinetic energy as it moves through the potential difference. The problem is resolved by applying the conservation of energy principle.
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Homework Statement



A particle with charge -3e is accelerated from rest through a potential difference of 200v .
This gives the particle a kinetic energy of?

Homework Equations





The Attempt at a Solution


what does a charge of -3e mean?(-3*2.71...?) to kind the KE wouldn't i need a mass too??
 
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e = charge of an electron.
Try using conservation of energy?
 
ok so the P.d = Ke??
I can't see that - can you give me a bit more please.
 
when a charged particle passes through a PotDif it "gains energy." (from the fields) since this is a particle of (assumed) no internal structure, the energy it gains will be in kinetic, not potential. Therefore you don't need a mass, the question just wants the energy.

the equation you need is indeed E = q.V (where q is the charge on the particle)

to better understand this, remember that we assume the particle does not "see" the potential when it is at an infinite distance from it (potential **difference** from that at infinity).
So in essence, the value of KinEn is how much the potential "wants" the particle to pass through it.
 
Last edited:
thanks Onamor - problem solved
 

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