Calculate i(t) for t>0 in the circuit of Fig. 8.82. 20u(-1) V

Introductory Circuit Analysis (13th Edition)
13th Edition
ISBN:9780133923605
Author:Robert L. Boylestad
Publisher:Robert L. Boylestad
Chapter1: Introduction
Section: Chapter Questions
Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...
icon
Related questions
Question

why the resistor disappear when t>0

Calculate i(t) for t> 0 in the circuit of Fig. 8.82.
F
20u(-1) V
Figure 8.82
For Prob. 8.34.
Chapter 8, Solution 34.
Before t= 0, the capacitor acts like an open circuit while the inductor behaves like a short
circuit.
i(0) = 0, v(0) = 20 V
For t> 0, the LC circuit is disconnected from the voltage source as shown below.
V,
i
(1/16)F
() H
This is a lossless, source-free, series RLC circuit.
1
a = R/(2L) = 0, w, = 1/ /LC = 1/.
V16
1
= 8, s= ±j8
4
Since a is less than o, we have an underdamped response. Therefore,
i(t) = Ajcos8t + A2sin8t where i(0) = 0 = A1
di(0)/dt = (1/L)vL(0) = -(1/L)v(0)= -4x20 = -80
However, di/dt = 8A2cos8t, thus, di(0)/dt = -80 = 8A2 which leads to A2 = -10
Transcribed Image Text:Calculate i(t) for t> 0 in the circuit of Fig. 8.82. F 20u(-1) V Figure 8.82 For Prob. 8.34. Chapter 8, Solution 34. Before t= 0, the capacitor acts like an open circuit while the inductor behaves like a short circuit. i(0) = 0, v(0) = 20 V For t> 0, the LC circuit is disconnected from the voltage source as shown below. V, i (1/16)F () H This is a lossless, source-free, series RLC circuit. 1 a = R/(2L) = 0, w, = 1/ /LC = 1/. V16 1 = 8, s= ±j8 4 Since a is less than o, we have an underdamped response. Therefore, i(t) = Ajcos8t + A2sin8t where i(0) = 0 = A1 di(0)/dt = (1/L)vL(0) = -(1/L)v(0)= -4x20 = -80 However, di/dt = 8A2cos8t, thus, di(0)/dt = -80 = 8A2 which leads to A2 = -10
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Latches and Flip-Flops
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Introductory Circuit Analysis (13th Edition)
Introductory Circuit Analysis (13th Edition)
Electrical Engineering
ISBN:
9780133923605
Author:
Robert L. Boylestad
Publisher:
PEARSON
Delmar's Standard Textbook Of Electricity
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:
9781337900348
Author:
Stephen L. Herman
Publisher:
Cengage Learning
Programmable Logic Controllers
Programmable Logic Controllers
Electrical Engineering
ISBN:
9780073373843
Author:
Frank D. Petruzella
Publisher:
McGraw-Hill Education
Fundamentals of Electric Circuits
Fundamentals of Electric Circuits
Electrical Engineering
ISBN:
9780078028229
Author:
Charles K Alexander, Matthew Sadiku
Publisher:
McGraw-Hill Education
Electric Circuits. (11th Edition)
Electric Circuits. (11th Edition)
Electrical Engineering
ISBN:
9780134746968
Author:
James W. Nilsson, Susan Riedel
Publisher:
PEARSON
Engineering Electromagnetics
Engineering Electromagnetics
Electrical Engineering
ISBN:
9780078028151
Author:
Hayt, William H. (william Hart), Jr, BUCK, John A.
Publisher:
Mcgraw-hill Education,