Two questions worth 14 points(gradpoint)
1. pu-239 has a half-life of

240 years
24 years
24,000 years
2,400 years
2. nuclear fusion has not yet been harnessed as an energy source because

sufficient pressure cannot be generated
lasers are too dangerous
of a lack of deuterium
the energy is hard to control

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