2.) A fluid moves in a steady manner between two sections in a flow line. At section 1: A2 = 10 ft?, V = 100 fpm, vl = 4 ftp/lb
At section 2: A2 = 2 ft², P2 = 0.20 lb/ft?
Calculate (a.) the mass flow rate, and
(b.) the speed at section 2

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?

What is the heat treatment of metals? what is the benefit of it? why and how it's useful? answer in details, do not write by hand.

To save energy, the air supply to a 2000 ft office has been shut off overnight and the room temperature has dropped to 40°f. in the morning, the thermostat is reset to 70°f and warm air at 120 f begins to flov in at 200ft'/min. the air is well mixed within the room, and an equal mass flow of air at room temperature (changing with time) is withdrawn through a return duct. the air pressure is nearly 1 atm everywhere. ignoring heat transfer with the surroundings and kinetic and potential energy effects, estimate how long it takes for the room temperature to reach 70°f. plot the room temperature as a function of time.