The ratio of drift velocities in the given two conductors of same materials A & B is :-

To answer this question, we need to understand the concept of drift velocity. Drift velocity is the average velocity that a particle, such as an electron, attains due to an electric field. It can be calculated using the formula:

Vd = I / (nAe)

Where: Vd = Drift velocity I = Current n = Number of charge carriers per unit volume A = Cross-sectional area of the conductor e = Charge of an electron

Given that the two conductors A and B are made of the same material, the number of charge carriers per unit volume (n) and the charge of an electron (e) will be the same for both.

Therefore, the ratio of drift velocities (VdA / VdB) will be equal to the ratio of the current to the cross-sectional area (IA / AA) divided by (IB / AB).

So, the ratio of drift velocities in the two conductors A and B is equal to the ratio of the current to the cross-sectional area in each conductor.