Author Question: The figure shows a steady electric current passing through a wire with a narrow region. What happens ... (Read 50 times)

future617RT · **on:** Jul 29, 2018

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 decreases from A to B and increases from B to C.
B) The drift velocity increases all the time.
C) The drift velocity remains constant.
D) The drift velocity decreases all the time.
E) The drift velocity increases from A to B and decreases from B to C.

Question 2

An air-filled capacitor stores a potential energy of due to its charge. It is accidentally filled with water in such a way as not to discharge its plates. How much energy does it continue to store after it is filled?

(The dielectric constant for water is 78 and for air it is 1.0006.)
A) 0.077 mJ
B) 468 mJ
C) 0.040 mJ
D) 6.00 mJ