Homework RL circuit

1. PRINCIPLES OF EE2
SEMESTER 1, ACADEMIC YEAR 2017 -2018
Homework No. 1
Deadline: 06/10/2017
Problem 1: RL circuit
In the circuit shown in Fig. 1, the switch has been in position a for a long time. At t = 0, it moves
instantaneously from a to b
a/ Find 𝑣0(𝑡) for 𝑡 ≥ 0;
b/ What is the total energy delivered to the 8Ω resistor;
c/ How many time constant does it take to deliver 95% of energy found in (b).
Fig. 1
Problem 2: RC Circuit
At the time the switch is closed in the circuit shown in Fig. 2, the capacitor are charged as shown.
a/ Find 𝑣0(𝑡) for 𝑡 ≥ 0+
;
b/ What percantages of the total energy initially store in the three capacitors is dissipated in the
250kΩ resistor;
c/ Find 𝑣1(𝑡) for 𝑡 ≥ 0;
d/ Find 𝑣2(𝑡) for 𝑡 ≥ 0;
e/ Find the enerdy trapped in the ideal capacitors.
Fig. 2

2. Problem 3: RLC Circuit
The switch in the circuit in Fig. 3 has been open for a long time before closing at t = 0.
a/ Find 𝑣0(𝑡) for 𝑡 ≥ 0+
;
b/ Find 𝑖 𝐿(𝑡) for 𝑡 ≥ 0+
;
Fig. 3
END
GOOD LUCK!