Twin-lead transmission lines (tls) are commonly used to connect tv sets and fm radios to their receiving antennas. for the twin-lead, the geometrical factor is gf = π cosh−1 d 2a , where 2a is the diameter of each wire (cylindrical conductor) of the twin lead, and d is the distance between the centers of the wires. assuming = o, µ = µo, and 2a = 1 mm, calculate d for twin lead tl's having: (a) zo = 50 ω and (b) zo = 300 ω.

Apump is used to circulate hot water in a home heating system. water enters the well-insulated pump operating at steady state at a rate of 0.42 gal/min. the inlet pressure and temperature are 14.7 lbf/in.2, and 180°f, respectively; at the exit the pressure is 60 lbf/in.2 the pump requires 1/15 hp of power input. water can be modeled as an incompressible substance with constant density of 60.58 lb/ft3 and constant specific heat of 1 btu/lb or. neglecting kinetic and potential energy effects, determine the temperature change, in °r, as the water flows through the pump.

Manometers are good examples of measuring instruments, nowadays they are not as common as before. a)-capacitive probe gauges b)-gravitational gauges deformation ) gauges d)-digital gauges

An air compression refrigeration system is to have an air pressure of 100 psia in the brine tank and an allowable air temperature increase of 60°f for standard vapor compression cycle temperatures of 77 f entering the expansion cylinder and 14 f entering the compression cylinder, calculate the coefficient of performance a. 2.5 b 3.3 c. 4.0 d. 5.0