If a storm is 7.5 kilometers away, how much time is expected between observations of lightning and thunder? Round
your answer to one decimal place.

Consider a resistor with color code “orange blue brown gold” and a measured value of 370 ω. determine the following: nominal value, tolerance, % error, and the probability of another resistor from the same manufacturing batch having a value closer to nominal than this one. use matlab or excel to evaluate the erf function.

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 of the following are not typically included in the periodic table? a. atomic mass b. element symbol c. isotopes d. number of electrons