two material bars A and B of equal area of cross section are connected in series to a DC SUPPLY. A image of usual resistance wire and B of a n-type semiconductor. In which wire drift speed of free electrons greater?
Answers
Two material bars A and B of equal area of cross section are connected in series to a DC SUPPLY. A image of usual resistance wire and B of a n-type semiconductor. In which wire drift speed of free electrons greater?
Considering the cross sectional areas of bar A and bar B are equal, we can decide that when we apply DC supply to material bar A, it gets resisted because the wire is resistive in nature and thus it reduces the drift speed of free electrons in bar A.
On the other hand, when we apply DC supply to material bar B, the drift speed is naturally higher than bar A because it is a n-type semiconductor which has a great number of free electrons by doping or adding impurities in it. These impurities like phosphorus (P), arsenic (As), antimony (Sb), or bismuth (Bi) are ready to donate free electrons for flowing the current through the semiconductor.
Hence, we can say that in bar B the drift speed of free electrons is greater than bar A.