Which of the following statements is true? a. the angle of refracted light is equal and opposite to the angle of incoming light. b. a magnetic field can be created by running an electric current through a magnet. c. exothermic chemical reactions absorb heat. d. velocity and temperature are scalar quantities.

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.

Which lists the pairs of plates in order from least to greatest in terms of the work done to move the electron?

You are doing a science experiment with a fahrenheit thermometer. your data must be in degrees celsius. if you measure a temperature of 125°f, what is this temperature in degrees celsius