Question

# 1. Brieflyanswer the following questions (8 pts each, 56 pts total) (a) Evaluate u(t) at t=0°. (b) Evaluate u(-t) at t=2 s. For t>0, find the time constant 7of the following circuit. Vs(iii) The complete response of the circuit below is i(t) =+ (6 - )e0.5t A, t>0, where Vs is a constant voltage. Determine the following response components. (a) Natural response in = (b) Forced response if = (c) Transient response ltr = (d) Steady-state response iss (iv) In the second-order circuit below, if L=4 H and C=0.01 F, determine the value of R which should be used to achieve critical damping. (v) Consider the RLC circuit below. Find vX0) and i(∞). (vi) Assume that RTH connecting to the 8 H inductor is 4 Q in the circuit below. If i(0) = 2 A,find the initial and final values of V(t). (vii) A 120 V generator drives a motor whose coil has an inductance of 100 mH and a negligible resistance. A field discharge resistor is connected in parallel with the motor to avoid damage to the motor. For t<0, the switch is closed, and the system is at steady state.(a) The switch suddenly opens at t=0. What is the maximum voltage dropping across the motor?(b) Why is the field discharge resistor needed to avoid damage to the motor?  Fig: 1  Fig: 2  Fig: 3  Fig: 4  Fig: 5  Fig: 6  Fig: 7  Fig: 8  Fig: 9  Fig: 10  Fig: 11  Fig: 12  Fig: 13  Fig: 14  Fig: 15  Fig: 16  Fig: 17  Fig: 18  Fig: 19