In unguided medium (free space), the electromagnetic (EM) signal wave spreads as it leaves the transmit antenna. Since the power of the EM signal resides in the surface area of the wave front, signal power is described as signal power density (i. e., watts per area). True

False

The spreading of an electromagnetic (EM) signal in an unguided medium such as air, weakens the EM signal therefore causing signal attenuation.

True

False

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

Abrayton cycle operates with a regenerator on the air-standard with properties evaluated at 400 k. the tem- perature of the air entering the compressor is 350k while the temperature of the air exiting the compressor is 600 k. the temperature of the air entering the turbine is 1600 k. the overall cycle produced 600 kj/kg of net work out. assuming a regenerator effectiveness of 0.8, what is the temperature of the air before heat addition (combustion)? draw this process on a t - s diagram

Agas mixture with a compostion of 55 methane, 30% propane, and 15 butane by volume) is compressed from 1 bar and 25°c to 9bar in a compressor with an isentropic efficiency of 85%. the environment has a temperature of to25 c. determine (a) the exit temperature of the mixture (b) the specific work required to run the compressor (c) the specific entropy generation of the process (d) the specific exergy destruction of the process (e) the second law efficiency of the compressor