Suppose 2 C of positive charge is distributed evenly throughout a sphere of 1.27 cm radius. (a) What is the charge per unit volume for this situation? C/m3 (b) Is the sphere insulating or conducting? How do you know? The sphere is conducting. If it were insulating, none of the charge would be in the interior of the sphere; it would only be on the surface. The sphere is insulating. If it were conducting, none of the charge would be in the interior of the sphere; it would only be on the surface. The sphere is conducting. If it were insulating, all of the charge would be in the interior of the sphere; not on the surface. The sphere is insulating. If it were conducting, all of the charge would be in the interior of the sphere; not on the surface.

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.

J. j. thomson’s experiment disproved the theory that an atom

Name two kinds of practical electric pumps.