A completely reversible heat pump produces heat at a rate of 100 kW to warm a house maintained at 25℃. The exterior air, which is at 0℃, serves as the source. Calculate the rate of entropy change of the two reservoirs and determine if this heat pump satisfies the second law according to the increase of entropy principle.

Coiled springs ought to be very strong and stiff. si3n4 is a strong, stiff material. would you select this material for a spring? explain.

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?

Which of the following refers to refers to how well the control system responds to sudden changes in the system. a)-transient regulation b)- distributed regulation c)-constant regulation d)-steady-state regulation