Author Question: A ring of negative, uniform charge density is placed on the xz-plane with the center of the ring at ... (Read 85 times)

gbarreiro · **on:** Jul 29, 2018

A ring of negative, uniform charge density is placed on the xz-plane with the center of the ring at the origin. A positive charge moves along the y axis toward the center of the ring.

At the moment the charge passes through the center of the ring A)

its velocity and its acceleration reach their maximum values.
B)

its velocity is maximum and its acceleration is zero.
C)

its velocity and its acceleration have non-zero values but neither is at its maximum.
D)

its velocity and its acceleration are both equal to zero.
E)

its velocity is zero and its acceleration is maximum.

Question 2

An LR circuit contains an ideal 60-V battery, a 51-H inductor having no resistance, a 21- resistor, and a switch S, all in series. Initially, the switch is open and has been open for a very long time. At time t = 0 s, the switch is suddenly closed.

When the voltage across the resistor is equal to the voltage across the inductor, what is the current in the circuit?
A) 0.86 A B) 1.7 A C) 1.1 A D) 0.57 A E) 1.4 A