The compound eyes of bees and other insects are highly sensitive to light in the ultraviolet portion of the spectrum, particularly light with a frequency between 6.0 ✕ 1014 Hz and 0.91 ✕ 1015 Hz. To what wavelengths do these frequencies correspond?

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.

Individuals who live below the poverty line get seriously ill more often than those who do not what could be the hidden variable in this situation?

What is the coefficient of kinetic friction μk between the block and the tabletop?