Angineering Physics II, Second Exam, Fall 2017, Dr. Chaves-Flynn. 10/19 MULTIPLE
ID: 3280905 • Letter: A
Question
Angineering Physics II, Second Exam, Fall 2017, Dr. Chaves-Flynn. 10/19 MULTIPLE CHOICE. Choose the alternatives that best completes the statement or answers the question. In where more than one statement is true you must indicate all the right choices to get full credit. 1) The figure shows a steady electric current passing through a wire with a narrow region. What happens to the drift velocity of the moving charges as they go from region A to region B and then to region C? A) The drift velocity increases all the time. B) The drift velocity increases from A to B and decreases from B to C. C) The drift velocity decreases from A to B and increases from B to C D) The drift velocity remains constant. E) The drift velocity decreases all the time.Explanation / Answer
The drift velocity is independent of the cross-sectional area so the drift velocity will be same for B and C.
Moreover, Resistance changes for B and C but since it is said that current is same between B and C therefore, the drift velocity must be constant. [answer - D]