Two long, parallel copper wires of diameters 2.3 mm carry currents of 7.0 a in opposite directions. (a) assuming that their central axes are separated by width w = 19 mm, calculate the magnetic flux per meter of wire that exists in the space between those axes. (b) what percentage of this flux lies inside the wires? (c) repeat part (a) for parallel currents.

Which two objects have the greatest gravitational force acting between them

As part of an industrial process, air as an ideal gas at 10 bar, 400k expands at steady state through a valve to a pressure of 4 bar. the mass flow rate of air is 0.5 kg/s. the air then passes through a heat exchanger where it is cooled to a temperature of 295k with negligible change in pressure. the valve can be modeled as a throttling process, and kinetic and potential energy effects can be neglected. (a) for a control volume enclosing the valve and heat exchanger and enough of the local surroundings that the heat transfer occurs at the ambient temperature of 295 k, determine the rate of entropy production, in kw/k. (b) if the expansion valve were replaced by an adiabatic turbine operating isentropically, what would be the entropy production? compare the results of parts (a) and (b) and discuss.

The mantle is made up of which structural zones?