. An N-type silicon sample has a uniform density Nd = 1016 cm–3 of arsenic, and a P-type sample has Na = 1017 cm–3 . A third sample has both impurities present at the same time. Find the Fermi level in each material at 300 K with respect to either the conduction band edge (Ec) or the valence band edge (Ev).

Water in a partially filled large tank is to be supplied to the roof top, which is 8 m above the water level in the tank, through a 2.2-cm-internal-diameter pipe by maintaining a constant air pressure of 300 kpa (gage) in the tank. if the head loss in the piping is 2 m of water, determine the discharge rate of the supply of water to the roof top in liters per second.

Water at the rate of 1 kg/s is forced through a tube with a 2.5 cm inner diameter. the inlet water temperature is 15°c, and the outlet water temperature is 50°c. the tube wall temperature is 14°c higher than the local water temperature all along the length of the tube. what is the length of the tube?

How to increase the thermal officiency of an ideal simple rankino cycle? among these methods, which one is the best and why?