Question

If two different wires having identical cross-sectional areas carry the same current, will the drift velocity be higher or lower in the better conductor? Explain in terms of the equation vd = I/(nqa), by considering how the density of charge carriers n relates to whether or not a material is a good conductor.

Answer 1

The drift velocity be higher for a good conductor.

Step-by-step explanation:

Drift velocity is the average velocity that an atom attains due to the electric field in the material.

Mathematically, drift velocity is given as:

`v_d=(I)/(n.a.q)`

where:

I= current in the conductor

n= charge density

a= cross-section area normal to the current flow

q= charge on the particle

From the above equation we find that drift velocity is inversely proportional to the charge density and we know that more is the density of the charge carriers better is the current conduction.

Hence for a better conductor the the value of charge carriers "n" will be higher resulting in a lower drift velocity.