A fluid of constant density is flowing in the z-direction through a circular pipe with axial symmetry. The radial direction is designated by r. (i) Using a cylindrical shell balance with dimensions dr and dz, derive the equation of continuity for this system. (ii) Use the equation of continuity in cylindrical coordinates to compare with the equation derived in (i).

Fluids at rest possess no flow energy. a)- true b)- false

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 ziegler nichols tuning methods the response of the controller to a step input should exhibit an s-shaped curve? a)-open loop mode b)-closed loop mode c)-both modes (open & closed) d)-none of the modes (open & closed)