Acurrent i flows down a long straight wire of radius a. if the wire is made of linear material (copper, say, or aluminum) with susceptibility χm, and the current is distributed uniformly,
what is the magnetic field a distance s from the axis? find all the bounf currents.
what is the net bound flowing down the wire?

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.

Which of the following is a direct benefit of the use of assembly lines in production a. laws against theft fraud and coercion are needed to protect free choice. b. the government needs to plan efficient outcomes. c. competition among producers by itself cannot ensure a wide range of consumer choices. d. works pressure the government to guarantee minimum wages

What practical value did astronomy offer to ancient civilizations?