Which sequence correctly shows how stars form?
a
nebula forms → nebula collapses → protostar forms → fusion begins
b
protostar forms → nebula forms → fusion begins → nebula collapses
c
fusion begins → nebula forms → protostar forms → nebula collapses
d
nebula forms → protostar forms → nebula collapses → fusion begins

Athin nonconducting rod with a uniform distribution of positive charge q is bent into a circle of radius r. the central perpendicular axis through the ring is a z-axis, with the origin at the center of the ring. a) what is the magnitude of the electric field due to the rod at z = 0? n/c (b) what is the magnitude of the electric field due to the rod at z = infinity? n/c (c) in terms of r, at what positive value of z is that magnitude maximum? r (d) if r = 4.00 cm and q = 9.00 µc, what is the maximum magnitude? n/c