- #1
LotusTK
- 36
- 0
Homework Statement
I am having a look at drift velocity and i know essentially what it is, and i am now noting down the factors that effect the drift velocity of the charge carriers as i think its a useful thing to know.
So, so far i have that the number of charge carriers will effect the velocity. The more charge carriers you have, the less quickly they must move in order to deliver a current.
If another material is to deliver the same current, and it has less charge carriers per m^3, then those fewer charge carriers will have to move more quickly in order to deliver the charge.
I have also noted down that increasing the temperature in a conductor will increase the vibrations of the ions in the material, creating more collisions for the electrons or charge carriers. Which will increase the resistance and decrease the current flowing through that material
Also, if the temperature is increased in a semi-conductor (which will have fewer free charge carriers), the atoms in that semi conductor will be given energy, and this energy will liberate more electrons and release them into the path of flow of the current, so this will then decrease the resistance, and increase the current. (or if the current were to remain the same, the drift velocity will decrease)
I think the above statements are correct??
I do not quite know how the charge of each carrier and the cross sectional area will effect the drift velocity though.
I think i am correct in saying that an increased current will result in a higher drift velocity? But then looking at the formula I=nVQA makes me think otherwise...
Homework Equations
I=nVQA
Current = #of charge carriers x Drift Velocity x Charge per carrier x Cross sectional Area