Goldberg's sleigh currently runs at 203mph, but he needs it to reach 400mph with all the packages he has to deliver.

if goldberg is delivering presents at an altitude of 5,813.6ft, with the same drag and weight of a 2019 challenger srt® hellcat redeye, how much hp would he need to reach 400 mph?
pro tips
100% driveline efficiency
p (air density) at 5813.6 ft = .0019 slug/ft^3
a (area of challenger front end) = 26.72 ft^2
c(d) (coefficient of drag) = .398
goldberg's sleigh required speed, 400 mph = 587 ft/sec
f(drag) = 1/2 p x v^2 x c(d)a
p = f(drag) x v
convert to horsepower = p ( 1hp/550 ft lbf/sec)

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.

Use the information presented in the graph to answer the questions. which segments show acceleration? which segment indicates that the object is slowing down? what is the velocity of segment b? what is the acceleration of segment b?

Find the magnetic field a distance r from the center of a long wire that has radius a and carries a uniform current per unit area j in the positive z direction.