Afour-port network with identical port characteristic impedances has the scattering matrix: [s] = 0.3∠−30◦ 0 0 0.8∠0 ◦ 0 0.7∠−30◦ 0.7∠−45◦ 0 0 0.7∠−45◦ 0.7∠−30◦ 0 0.8∠0 ◦ 0 0 0.3∠−30◦ (2) (a) is this network lossless? (b) is this network reciprocal? (c) what is the return loss at port 1 when all other ports are terminated with matched loads? (d) what is the insertion loss and phase delay between ports 2 and 3, when all other ports are terminated with matched loads? (e) what is the reection coecient seen at port 1 if a short circuit is placed at the terminal plane of port 4, and all other ports are terminated with matched loads?

Afour cylinder four-stroke in-line engine has a stroke of 160mm, connecting rod length of 150mm, a reciprocating mass of 3kg and its firing order is 1-3-4-2. the spacing between cylinders is 100mm. i. show that the engine is in balance with regard to the primary inertia forces and primary 3. a and secondary inertia couples. li determine the out of balance secondary inertia force ii. propose ways of balancing this out of balance force and discuss the challenges that will arise

Condition monitoring is a major component of. (clo4) a)- predictive maintenance. b)-preventive maintenance c)-proactive maintenance d)-reactive maintenance.

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg. m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?